MINISTRY OF EDUCATION AND TRAINING HO CHI MINH CITY OPEN UNIVERSITY Field of Study: TESOL Field of Study Code: 9140111 BUI NGUYEN NGUYET MINH SUMMARY OF DOCTORAL DISSERTATION Investigati
Background to The Study
English has become a global lingua franca, with 80% of its users being non-native speakers, leading to diverse forms influenced by local languages and cultures Pronunciation, historically overlooked in second language acquisition research, has gained importance since 2005 due to its critical role in intelligibility The emphasis has shifted from achieving native-like accents to fostering mutual understanding, encouraging more inclusive pronunciation standards.
In Vietnam, English teaching incorporates global methodologies such as Communicative Language Teaching (CLT), Task-Based Approach (TBA), and the Flipped Learning Approach, which focus on enhancing communication skills and improving pronunciation However, the effectiveness of these methods is contingent upon the preparation of teachers and the quality of teaching materials Despite their potential, challenges persist, including an overemphasis on grammar and vocabulary, large class sizes, and a primary focus on segmental features of language, often overlooking important aspects like intonation and rhythm.
Despite initiatives like the Vietnam National Foreign Language Project, pronunciation results have varied significantly A key difficulty is the instruction of English voiceless consonants, including /p/, /t/, /k/, /f/, /θ/, and /s/, which present articulation challenges for Vietnamese learners Additionally, the influence of Vietnamese tones affects the perception and production of these consonants, complicating the distinction of English stops.
2021) Additionally, Vietnamese typically features unreleased final stops, contrasting with English’s released ones (Horn & Pham, 2004) These differences create persistent difficulties in teaching voiceless consonants to Vietnamese EFL learners
Statement of the Problem
Vietnamese learners of English often face challenges in pronouncing voiceless consonants, leading to communication issues (Bui et al., 2024) This difficulty arises from key differences in the sound systems of English and Vietnamese, both at the segmental level (individual sounds) and the suprasegmental level (stress, rhythm, and intonation) Many learners find it hard to articulate English voiceless sounds such as /p/, /t/, /k/, /θ/, and /ʃ/ due to the absence of equivalent sounds in Vietnamese and distinct articulation rules, including the lack of aspiration in stops and the tendency to replace unfamiliar fricatives with native sounds (Thai & Nguyen, 2023; Do, 2024).
Common pronunciation errors among Vietnamese learners include omission, such as dropping the /t/ sound in "street," as well as substitution and assimilation, where sounds blend unnaturally in connected speech Research indicates that nearly 90% of these learners struggle with pronouncing final voiceless consonants.
In 2023, intelligibility issues in English language learning are exacerbated by the influence of Vietnamese, a tonal and syllable-timed language This linguistic background impacts learners' ability to perceive and produce stress and intonation in English, as highlighted by Thach & Nguyen (2024) and Le & Tran (2024).
In Vietnam, pronunciation instruction primarily emphasizes segmentals and physical articulation, often overlooking cognitive and perceptual elements, despite the implementation of global teaching methods such as Communicative Language Teaching (CLT) and flipped learning Additionally, large class sizes and insufficient feedback impede learners' progress in improving their pronunciation skills.
Improving the pronunciation of voiceless consonants is crucial for enhancing intelligibility and boosting learners' confidence in English Research indicates a need to transition from solely training articulatory movements to improving auditory perception, enabling learners to discern subtle differences between English and Vietnamese sounds This focus on perception aligns with the brain's language processing, as consistent practice allows the subconscious to manage pronunciation, resulting in more fluent and effortless speech.
A fresh strategy is essential to highlight prosody—encompassing intonation, rhythm, and stress—while utilizing technology for self-directed learning and fostering habit formation through consistent auditory practice This transformation will empower learners to develop enduring pronunciation skills that extend beyond traditional classroom exercises, facilitating more natural and comprehensible speech in everyday interactions.
Research Aims and Purposes of this Study
This study explores the effectiveness of the Simplified Verbotonal Approach in teaching voiceless consonants to Vietnamese undergraduates who are not majoring in English The research is guided by two key objectives to assess the impact of this teaching method.
This study investigates the influence of the Simplified Verbotonal Approach on the pronunciation of voiceless consonants in Vietnamese non-English major undergraduates, contrasting it with traditional teaching methods The research assesses this impact across group, individual, and linguistic levels, including words, sentences, and passages.
To examine Vietnamese non-English major undergraduates’ opinions on the satisfaction and perceived effectiveness of using the Simplified Verbotonal Approach in learning the pronunciation of voiceless sounds
Research Questions
1 To what extent does the Simplified Verbotonal Approach impact the pronunciation of voiceless consonants among Vietnamese non-English major undergraduates compared to the conventional approach at the group, individual, and linguistic levels?
2 What are Vietnamese non-English major undergraduates’ opinions on the satisfaction and perceived effectiveness of using the Simplified Verbotonal Approach in learning the pronunciation of voiceless sounds?
The Significance of the Study
This study significantly enhances pronunciation teaching for Vietnamese EFL learners by introducing the Simplified Verbotonal Approach, which emphasizes prosody—intonation, rhythm, and stress—over traditional segmental instruction By utilizing a top-down, prosody-driven model, this approach promotes more natural speech patterns and improves the perception and production of voiceless consonants Additionally, it incorporates Computer-Assisted Language Learning (CALL) to create a flexible, tech-supported environment that fosters independent learning The study also adapts the Traditional Verbotonal Approach to better suit the Vietnamese context, providing strong empirical evidence that supports the Simplified Verbotonal Approach as a more effective alternative to conventional methods.
Practically, the study offers a straightforward, structured approach that can be easily implemented
Scope of the Study
This study examines the impact of the Simplified Verbotonal Approach on the pronunciation of voiceless consonants among Vietnamese non-English major undergraduates By concentrating exclusively on voiceless consonants, the research aims to deliver specific insights into pronunciation accuracy and intelligibility across group, individual, and linguistic levels Conducted during the 2022–2023 academic year at a public university in Ho Chi Minh City, the study employs a quasi-experimental mixed-method design, utilizing data from pronunciation tests, interviews, and learners’ logs Seventy students participated, divided into experimental and control groups, and practiced voiceless sounds in a computer-equipped language lab with personalized feedback The structured learning environment is designed to provide clear evidence of the effectiveness of the Simplified Verbotonal Approach in enhancing pronunciation skills.
Definitions of Key Terms
The Traditional Verbotonal Approach, created by Guberina in the 1950s, utilizes auditory, visual, and kinesthetic cues to enhance pronunciation and prosody This method differs from the Simplified Verbotonal Approach (SVA) implemented in this study.
The conventional Approach typically follows a bottom-up model, focusing on phonetic drills, IPA symbols, and articulatory explanations, prioritizing segmental accuracy before suprasegmentals
A computer-based pronunciation platform was created specifically for this study to support learners in improving voiceless consonant production through SVA principles
An approach is the philosophy of language learning, a method is the structured plan for applying that philosophy, and techniques are specific activities or tools used to address learning goals
Intonation-pattern exercises help learners differentiate pitch variations in speech, aiding pronunciation and comprehension
Voiceless consonants are sounds produced without vocal cord vibration (e.g., /p/, /t/, /k/), which can be challenging for Vietnamese learners
Formant transitions refer to the acoustic changes in speech that occur as articulators move between sounds, helping listeners distinguish between different consonants and vowels.
Organization of the Study
This study is organized into five chapters, each building on the last to guide the reader through the research journey
Chapter 1 lays the groundwork by introducing the problem, research aims, and improving pronunciation, particularly voiceless consonants
Chapter 2 reviews relevant literature, covering pronunciation teaching approaches, the Traditional Verbotonal Approach, and gaps that justify this study
Chapter 3 details the research design, including methods like tests, interviews, and learners ' logs, and addresses ethical considerations to ensure validity and reliability
Chapter 4 presents and interprets the findings using tables and figures, showing improvements in pronunciation and comparing results to existing studies
Chapter 5 wraps up the study by summarizing its contributions, offering practical recommendations, and suggesting directions for future research.
REVIEW
Understanding Pronunciation in English
Grasping the key elements of English pronunciation, including both segmental and suprasegmental features, is crucial for evaluating their effects on intelligibility and communication skills This section will provide a detailed analysis of these aspects.
Pronunciation in any language encompasses two main categories: segmental features, which include phonemes such as consonants and vowels, and suprasegmental features, known as prosodies, which pertain to the characteristics of extended speech (Pennington & Rogerson-Revell, 2019, p.3).
Segmentals, which include individual sounds known as phonemes, are the building blocks of words and sentences (Wang, 2022; Hewings, 2004) Consonants are articulated by obstructing airflow, as seen in sounds like /p/ and /m/, whereas vowels permit a more open airflow, influenced by the positioning of the mouth (Rogerson-Revell, 2017).
Speech sounds are characterized by the vibrations of the vocal folds and the resonances within the vocal tract, which are quantified by formant frequencies (Ladefoged & Johnson, 2014) Distinct patterns in these frequencies, particularly among various nasals and approximants, play a crucial role in differentiating sounds.
Voiceless consonants play a crucial role in ensuring speech clarity and intelligibility Their articulation and acoustic characteristics greatly affect learners' perception and production, particularly in second-language acquisition This study highlights the impact of prosody on learners' ability to accurately hear and pronounce voiceless consonants.
Voiceless consonants play a crucial role in speech clarity and are the focus of this study English features nine voiceless consonants—plosives, fricatives, and affricates—classified by their place and manner of articulation In contrast to Vietnamese, English employs aspiration, friction, and bursts of air to differentiate these sounds, which can be absent or produced differently in Vietnamese This discrepancy poses significant challenges for Vietnamese learners in accurately recognizing and pronouncing these sounds in various word positions.
The acoustic characteristics of consonants, including formant transitions and burst noise, are crucial for sound differentiation (Ladefoged & Johnson, 2014) However, Vietnamese learners frequently struggle with final sounds and similar consonants, often misinterpreting English stress as tone, which negatively impacts their intelligibility (Tran & Nguyen, 2022).
The Simplified Verbotonal Approach (SVA) focuses on enhancing auditory perception before speech production, addressing key challenges in language learning By emphasizing important acoustic cues such as aspiration, duration, and pitch variation, SVA enables learners to recognize subtle sound differences that might otherwise go unnoticed The use of filtered sentences in SVA highlights these acoustic features, allowing learners to internalize and naturally replicate them in their speech This method effectively bridges the gap between perception and production, resulting in clearer and more fluent pronunciation of voiceless consonants.
Suprasegmentals, or prosody, play a vital role in effective pronunciation and communication, encompassing rhythm, stress, and intonation (Seidlhofer, 2001; Fujisaki, 1997) Unlike individual phonemes, prosodic features influence the structure and comprehension of speech, conveying both linguistic meaning and the speaker's emotions and intentions Inadequate prosody can result in misunderstandings, even when phonetic sounds are articulated correctly (Fraser, 2001).
Research indicates that prosody significantly affects the production of voiceless consonants, with stress and intonation influencing the pronunciation of sounds like /p/, /t/, and /k/ (Celce-Murcia et al., 2010; Hahn, 2004) Two primary teaching models—bottom-up and top-down—provide distinct approaches to mastering pronunciation, with studies favoring the top-down method for its effectiveness in enhancing speech intelligibility (Dalton & Seidlhofer, 1994; Kang et al., 2010; Couper, 2015; Dahmen et al., 2023) The Simplified Verbotonal Approach employs this prosody-first strategy, aiding Vietnamese learners in better perceiving and producing voiceless consonants, ultimately improving their fluency and clarity through a focus on intonation patterns and rhythmic structures.
Segmental accuracy is important, but prosodic awareness is crucial for achieving intelligibility and natural communication By emphasizing suprasegmental training, especially in intonation, learners can greatly enhance their pronunciation and overall communicative effectiveness.
Intonation, the variation in pitch during speech, plays a crucial role in pronunciation and effective communication As a key component of prosody, it conveys emotional, grammatical, and emphatic meanings, allowing speakers to differentiate between statements, questions, and emphasis through distinct rising or falling pitch patterns These patterns enable listeners to grasp meanings that extend beyond the literal words spoken.
Intonation significantly affects the production and perception of voiceless consonants in connected speech Aspiration in sounds like /p/, /t/, and /k/ varies with stress and pitch, being more pronounced in stressed syllables and less so in unstressed ones Vietnamese learners, unfamiliar with the stress-timed rhythm and pitch-based meanings of English, often mispronounce or omit these consonants, particularly in rapid or natural speech.
The SVA incorporates intonation training through filtered recordings that highlight pitch variations, aiding learners in distinguishing sounds and understanding the interaction between pitch and voiceless consonants This method enhances their perception of pitch and rhythm, effectively connecting auditory recognition with accurate sound production Through consistent exposure and practice, learners achieve improved phoneme accuracy and develop a more natural fluency in their speech.
In summary, intonation significantly influences the understanding and production of sounds The SVA utilizes this concept by emphasizing the perceptual effects of intonation patterns, which helps Vietnamese learners achieve clearer and more intelligible pronunciation Future research will investigate the interplay between perception and production in the context of pronunciation learning.
2.1.1.5 Perception and Production in Learning Pronunciation
Approaches to English Pronunciation Instructions
This section outlines essential pronunciation teaching methods, such as the top-down approach, Computer-Assisted Language Learning (CALL), and fundamental learning theories, which collectively create a robust framework for enhancing pronunciation skills effectively.
2.2.1 Evolution of the Pronunciation Teaching Approach
The evolution of pronunciation teaching has transitioned from traditional methods centered on repetition and sound drills, such as the Direct Method and Audiolingualism, to more communicative and learner-centered approaches like Communicative Language Teaching (CLT), Suggestopedia, Task-Based Language Teaching (TBLT), and the Natural Approach These contemporary methods prioritize the integration of pronunciation within authentic communication, focusing on fluency, interaction, and a stress-free learning environment.
Many learners face difficulties with voiceless consonants in English due to differences between their first language (L1) and English (L2) This challenge has sparked renewed interest in the contrastive analysis approach, as proposed by Lado in 1957, which aids learners in comparing sounds from their L1 and L2 to better understand and rectify errors stemming from negative transfer.
Contrastive analysis is insufficient on its own; this study introduces a novel approach focused on perceptual training and self-awareness By providing learners with frequent exposure to intonation patterns and prosody, the method aims to help them internalize subtle sound features The objective is to transition pronunciation from a conscious effort to automatic and accurate speech production, minimizing dependence on teacher guidance, which may be hindered by accent variation, inadequate training, and subjective biases (Derwing & Munro, 2005; Underhill, 2010).
To address pronunciation challenges, the study advocates for a top-down approach that begins with prosody—encompassing intonation, rhythm, and stress—before progressing to segmental accuracy This method enables learners to produce clearer and more natural speech by emphasizing intelligibility and communicative effectiveness rather than striving for native-like precision The next section will examine how top-down strategies improve pronunciation instruction by concentrating on suprasegmental features.
2.2.2 Top-down Approaches in Teaching Pronunciation
Bottom-up instruction targets individual sounds, while top-down approaches prioritize meaningful communication by incorporating suprasegmental features such as stress, rhythm, and intonation This shift has been shown to significantly improve learners' intelligibility, according to research.
The researcher employs a top-down approach to teaching voiceless consonants, highlighting their variation in real-life contexts influenced by prosody and sentence position This method differs from isolated drills by integrating pronunciation into authentic communication, which aligns with communicative teaching objectives.
Top-down techniques in language learning emphasize the significance of teaching intonation in context, as highlighted by Pickering (2001) in his work with international teaching assistants Shadowing, discussed by Luo et al (2008), allows learners to mimic native speech patterns but falls short in providing social and contextual cues To enhance this, mirroring techniques proposed by Meyers (2013) and adaptations by Rojczyk (2015) encourage learners to imitate not only sounds but also facial expressions and emotional tones, fostering more natural and expressive speech.
Many current methods prioritize production over perception, hindering learners' ability to discern subtle sound differences To address this issue, the researcher introduces the SVA, a refined top-down approach that starts with perceptual training By utilizing filtered intonation patterns, SVA enhances learners' sensitivity to prosody, allowing them to internalize variations in pitch, stress, and rhythm This leads to more fluent and accurate pronunciation that becomes automatic over time.
The SVA utilizes top-down principles while emphasizing perception as the key to natural speech production, effectively addressing shortcomings in previous methods It equips learners to achieve accurate and contextually relevant pronunciation The next section will examine how CALL and CAPT technologies enhance these objectives.
Computer-Assisted Language Learning (CALL) and Computer-Assisted Pronunciation Training (CAPT) have transformed pronunciation instruction by providing interactive and personalized learning experiences These technologies overcome the limitations of traditional methods by incorporating visual aids, real-time feedback, and speech recognition, which assist learners in improving both segmental features, such as voiceless consonants, and suprasegmental features, including intonation and rhythm CALL platforms facilitate individualized learning, enabling learners to advance at their own pace through structured drills and audio-visual feedback CAPT further enhances auditory discrimination with tools like spectrograms and synthetic speech, aiding learners in recognizing and producing subtle sound differences, particularly in distinguishing voiceless consonants Tools like ELSA Speak exemplify these advancements in pronunciation training.
AI, offer tailored exercises and instant feedback on pronunciation errors, helping learners refine voicing, aspiration, and sound clusters
CAPT systems enhance language learning by visualizing intonation contours and stress patterns, enabling learners to analyze pitch and rhythm both visually and aurally These systems facilitate real-time comparisons of learners' prosodic features with native models, allowing for immediate pronunciation adjustments Research indicates that CAPT significantly boosts pronunciation skills, particularly in classroom and higher education contexts.
While CALL and CAPT focus on production, potentially hindering perceptual growth, the SVA presents a complementary approach by emphasizing perception through filtered intonation patterns This method minimizes L1 interference and directs learners' focus to prosody and natural rhythm, enabling them to internalize voiceless consonants before progressing to structured articulation.
In conclusion, CALL and CAPT are effective tools for modern pronunciation teaching, providing visual feedback, repetition, and speech recognition The SVA enhances this by incorporating perceptual training, which aids learners in grasping prosodic patterns for more natural and fluent pronunciation The next section will discuss low-pass filtering, a technique utilized in SVA, which reinforces this perceptual foundation by isolating rhythm and pitch from segmental distractions.
Low-pass filtering is an effective signal processing technique that aids learners in focusing on rhythm, stress, and intonation by eliminating distracting high-frequency phonemic details This method is particularly significant in pronunciation teaching within the SVA, as it enhances prosodic awareness before learners refine their articulation of individual phonemes By filtering out segmentals, learners can better grasp the melody and rhythm of speech, which is vital for achieving intelligibility and fluency in a second language Research indicates that filtered speech improves learners' perception of stress and rhythm (Sonntag & Portele, 1997), strengthens prosodic patterns (IBA, 2009), and enhances segmental accuracy later on (Luu et al., 2021) Additionally, it reduces cognitive load, facilitating the absorption of the natural flow of English, particularly for learners from syllable-timed language backgrounds.
The Verbotonal Approach: From Tradition to Innovation
This section discusses established foundational theories and guiding principles of TVA, reviews previous studies on the topic, and identifies research gaps
2.3.1 Theories Underlying the Traditional Verbotonal Approach
TVA, created by Guberina, highlights the importance of spoken language and its connection to social, cultural, and individual contexts Influenced by Saussure’s idea of “parole” and Bally’s emphasis on expressive language, TVA perceives language as a dynamic oral phenomenon influenced by rhythm, intonation, tempo, and body language Guberina posits that both speech and non-verbal cues collectively constitute a comprehensive communication system.
TVA’s theory emphasizes the importance of non-lexical elements like pitch, stress, pauses, and gestures in conveying meaning By integrating insights from linguistics, psychology, and education, it adopts a multidisciplinary and multimodal approach to foster a rich learning environment.
The SVA, developed for Southeast Asian learners, modifies the TVA framework by emphasizing prosody, teaching sounds in context, and incorporating customized techniques to mitigate first-language interference This approach facilitates perception-to-production learning, transitioning from conscious awareness to automatic pronunciation.
2.3.2 Core Principles of the Traditional Verbotonal Approach
TVA, created by Guberina, offers a comprehensive approach to pronunciation teaching and speech rehabilitation, initially designed for children with hearing impairments Its relevance in language instruction persists due to its emphasis on auditory perception, suprasegmental features such as intonation, rhythm, and pitch, as well as the integration of verbal and non-verbal cues Grounded in theories like Trubetzkoy’s phonological sieve and research by Ellis (2004), TVA highlights that mispronunciations often stem from learners filtering foreign sounds through their native language.
The TVA approach emphasizes that accurate pronunciation is rooted in accurate sound perception, as learners must first adjust their auditory processing before they can produce sounds correctly This principle is backed by researchers such as Asp & Guberina (1981), Gilakjani (2016), and García (2018) By focusing on suprasegmentals rather than isolated phonemes, TVA employs a top-down learning model that mirrors the natural language development observed in children.
TVA integrates body movement into speech learning by utilizing Laban’s Movement Analysis, emphasizing the connection between gestures and pronunciation Non-verbal cues enhance verbal expression and are particularly beneficial in tonal languages Teachers are essential in TVA, as they identify speech perception challenges, model accurate pronunciation, provide feedback, and adapt their methods to meet the diverse needs and cultural backgrounds of learners (Tuta Dujmović et al., 2023) Similar to infants acquiring language, second-language learners advance through stages of perception, imitation, and production TVA facilitates this natural learning process, enabling learners to internalize pronunciation patterns over time.
TVA emphasizes perception, prosody, body movement, and personalized instruction, making it an effective method for teaching pronunciation in second-language settings This section examines the application of these principles in empirical research.
2.3.3 Review of Previous Studies on the Traditional Verbtonal Approach
Lian (1980) introduced TVA to teaching French pronunciation Developed techniques such as relaxation phases, sentence filtering, gestures, and repetition exercises to improve pronunciation by focusing on rhythm and intonation
Klein (2010) utilized the TVA to enhance phonetic correction for Japanese learners of English, focusing on the use of gestures to assist with pronunciation, particularly for challenging consonant sounds and intonation However, he also pointed out the drawbacks of over-relying on gestures in real-life communication.
He and Sangarun (2015) utilized the TVA to enhance the comprehensibility and fluency of English majors Their approach emphasized relaxation, low-pass filtered intonation, and involved engaging learners in rhythmic activities such as clapping and walking in rhythm to improve their prosody perception.
Yang et al (2017) implemented TVA to enhance English-speaking skills by conducting structured in-class sensitization sessions These sessions included relaxation techniques, filtered listening exercises, body movements, and interactive dialogues, all aimed at improving students' pronunciation and fluency.
García (2018) suggested techniques for phonetic correction for Spanish learners using a playful and practical environment He recommended using software like Praat to visualise and correct prosody through spectrograms and waveforms
Wen (2019) focused on improving the pronunciation of English vowels for Chinese students using TVA and emphasised filtering vowel sounds and progressive activities that measured optimal vowel frequency
Cai et al (2021) explored TVA principles in dichotic listening and low-pass filtering to identify optimal audio-language input for Chinese learners of English, revealing that various filtered and unfiltered signals activate different brain hemispheres to enhance language acquisition Similarly, Luu et al (2021) evaluated the effectiveness of TVA in improving listening skills among EFL learners by employing low-pass filtering and body movement to retrain auditory perception and boost comprehension.
2.3.4 Research Gaps Identified in Current Literature
TVA-based studies significantly improve pronunciation by combining auditory perception, body movement, prosodic training, and teacher guidance Researchers have implemented TVA principles in diverse educational and cultural contexts to enhance learners' phonetic skills, focusing on low-pass filtering, prosodic awareness (including intonation, rhythm, and pitch), and physical movement to strengthen auditory memory and pronunciation accuracy The role of teacher guidance is crucial, as it involves modeling pronunciation, offering feedback, and facilitating learners' phonological development.
Various studies employ diverse techniques to enhance language learning, such as filtered sentence repetition, gesture-supported pronunciation, visual feedback using Praat software, dichotic listening, and web-based prosody training Regardless of the setting—be it traditional classrooms, laboratory environments, or online platforms—these studies are unified by the TVA foundation, which aims to alter learners' perceptions to improve their production skills.
Instructional procedures are organized into structured sequences that begin with relaxation or awareness-raising phases, followed by prosody-focused activities such as humming, body movement, shadowing, or silent mouthing These procedures often incorporate teacher-led corrections, pronunciation games, and role-play Research by Yang et al., Wen, and García highlights multi-step instructional designs aimed at achieving specific phonetic objectives.
Traditional TVA applications face significant limitations due to their dependence on teacher-led instruction and physical movement, which can restrict scalability and accessibility, particularly in resource-limited settings or cultures with specific constraints.
Related studies about learners’ satisfaction and the effectiveness of pronunciation
Pronunciation plays a crucial role in effective communication and boosting learner confidence, making it essential to assess both instructional effectiveness and learner satisfaction Satisfaction encompasses learners' confidence, motivation, and belief in the value of the instruction (Horwitz, 1988; Zhang & Rahimi, 2014) Research by Couper (2006) and Derwing & Munro (2015) indicates that instruction is more impactful when it relates to real-life communication and enhances learner confidence Additionally, Sardegna (2023) highlights the importance of learner ownership and self-directed practice, which is supported by the SVA's prosody-focused design.
Effectiveness in learning is determined not just by test scores, but also by learners' perceptions of intelligibility, fluency, and control According to Sardegna’s Enhanced-CRM, establishing clear goals, providing feedback, and encouraging reflection significantly enhance motivation and engagement Saito (2011) supports the idea that explicit instruction combined with feedback leads to improvements in both segmental and suprasegmental accuracy Overall, instruction that is emotionally supportive and goal-oriented increases satisfaction, encourages practice, and leads to better pronunciation outcomes (Derwing & Munro, 2015; Sardegna, 2023) These findings inform the conceptual framework for examining the impact of SVA in this study.
Conceptual Framework
The literature review establishes the theoretical basis for this study's conceptual framework The SVA revolutionizes pronunciation teaching by prioritizing prosody and minimizing gestures and teacher intervention, aligning with educational theories such as Behaviorism, Cognitivism, Connectivism, and Constructivism This approach fosters a self-directed, technology-driven learning environment where learners actively engage with prosodic features, utilizing intonation filtering to recognize subtle acoustic distinctions essential for pronouncing voiceless consonants without first language interference The SVA emphasizes perception, production, and prosody, employing techniques that enhance learners' self-directed learning and pronunciation abilities By focusing on learner independence and digital learning, the SVA serves as an effective model for teaching voiceless consonants without direct teacher involvement, integrating modern educational theories to improve pronunciation training, as illustrated in the conceptual framework in Figure 2.2.
Figure 2.2: Conceptual Framework of this Study
Research Paradigm
Pronunciation acquisition is a multifaceted process that involves both objective and subjective assessments This study utilizes a postpositivist approach to evaluate the effectiveness of the SVA in enhancing voiceless consonant pronunciation among Vietnamese non-English majors By integrating positivist techniques, such as pre- and post-tests, with constructivist perspectives on learner perceptions, the research employs a mixed-methods design that effectively captures both quantifiable results and personal experiences.
Research Design
This study employs a quasi-experimental mixed-methods design to assess the impact of SVA on voiceless consonant pronunciation The quantitative phase involves evaluating pre- and post-test learning gains through t-tests or ANOVA, while qualitative data from interviews and learner logs provide insights into learners' satisfaction, effectiveness, and challenges By merging both data types after separate analyses, the study aims to enhance understanding of outcomes and learner experiences, thereby increasing the validity of the findings The subsequent section outlines the sampling strategy that supports this design.
Sampling
This research utilized a sampling method based on the pilot phase, focusing on first-year non-English major students to evaluate the effectiveness of the Simplified Verbotonal Approach (SVA) for pronunciation improvement A total of 150 participants were involved, divided into pilot and main study groups, which provided sufficient statistical power to assess the SVA's impact.
The study focused on 70 non-English major students enrolled in English Level 1 at University “A,” who came from various academic backgrounds and lacked specialized training in pronunciation This diversity and absence of prior pronunciation instruction made them suitable candidates for assessing the effects of a teaching intervention on pronunciation skills.
Participants were selected based on consistent inclusion and exclusion criteria from the pilot phase, specifically targeting beginner-level learners This strategic choice is significant as non-English majors face more authentic pronunciation challenges, making them ideal for studying common pronunciation errors (Jarosz et al., 2019) They represent a wide segment of English learners globally, enhancing the generalizability of the findings Furthermore, non-English majors typically have less exposure to comprehensive pronunciation training compared to their English major counterparts, which minimizes the impact of prior learning habits and allows for better control over experimental conditions (Jarosz et al., 2019).
Early-stage learners often begin with lower pronunciation skills, which allows for significant improvement, as noted by Jarosz et al (2019) These learners tend to demonstrate more visible progress compared to advanced students, whose enhancements are less pronounced Additionally, non-English majors may experience increased motivation and better learning outcomes when exposed to professional teaching methods, further enhancing their engagement (Jarosz et al., 2019).
The Implementation of the Intervention
This section presents the teaching syllabus, materials, and procedures used for the experimental and control groups
3.4.1 The Teaching Syllabus and Materials
This section outlines the integration of the teaching syllabus and materials into the instructional process for both the control and experimental groups, detailing their implementation in the training sessions
3.4.1.1 The Teaching Syllabus and Materials for C-GRP
The Control Group (C-GRP) followed a ten-week syllabus based on Ann Baker’s Ship or Sheep
In 2006, a comprehensive pronunciation textbook was developed, emphasizing one voiceless consonant each week through minimal pairs and phonetic drills to enhance articulation and prosodic awareness The syllabus featured consistent instructional steps, including sound introduction, guided articulation, minimal pair practice, and contextual exercises To ensure its effectiveness, the syllabus was validated by pronunciation teachers and experts, aligning it with standard curricula and ensuring comparability with the experimental group.
3.4.1.2 The Teaching Syllabus and Materials for E-GRP
The Experimental Group (E-GRP) utilized a researcher-designed syllabus that integrated the SVA, emphasizing prosody and sentence-level practice through an online platform In contrast to the Control Group, which focused on segmental articulation, the E-GRP engaged in weekly practice of five context-based sentences targeting voiceless consonants across various sentence types, including statements, questions, and exclamations Key techniques employed in the E-GRP included low-pass filtered speech to enhance prosodic focus and minimize L1 interference, intonation-based drills to improve rhythm and pitch awareness, and self-monitoring through comparisons with native models to encourage independent correction.
The syllabus, validated by experts and tested for comparability, provided targeted exposure to specific sounds in various word positions It included fifty carefully selected sentences featuring sounds such as /p/, /t/, /k/, /f/, /θ/, /s/, /ʃ/, /h/, and /tʃ/, which facilitated systematic improvement (Celce-Murcia et al., 2010; Derwing & Munro, 2015) A distinctive aspect of the approach was the use of Text-to-Speech (TTS) technology to create model sentences, which were enhanced through full low-pass filtering for prosodic training and dichotic filtering (Cai et al., 2021) to minimize cognitive load and enhance intelligibility.
The platform monitored learner engagement through tracking login frequency and practice time, showcasing an innovative use of TTS in verbotonal-based instruction This approach has significant implications for personalized language learning.
This section describes the pedagogical approaches employed and attempts to clarify the theoretical underpinnings of SVA and the conventional approach for pronunciation instruction
3.4.2.1 Teaching Procedure for Control Group
The Control Group engaged in a standard pronunciation syllabus over 10 weeks, utilizing "Ship or Sheep" (Baker, 2006) with 2 hours of instruction each week, similar to the Experimental Group (E-GRP) A university lecturer with equivalent teaching experience conducted the lessons, strictly following the pre-designed syllabus and providing regular updates to the researcher To ensure the validity of the quasi-experimental design, the researcher refrained from teaching this group to prevent intervention bias (Chow, 2024; Reichardt, 2009) The teaching protocol included warm-up activities like tongue twisters, sound demonstrations with audio, diagrams, and mirrors, along with individual and group practice, written tasks, and reflective sessions at the end of each class.
Students participated in 45 minutes of daily home practice using shared audio materials and student logs, as outlined by Pennington & Rogerson-Revell (2019) While both groups' logs were monitored for balanced engagement, the E-GRP utilized a self-directed model, whereas the C-GRP benefited from teacher reminders.
3.4.2.2 Teaching Procedure for Experimental Group
The Experimental Group participated in self-directed learning via a researcher-created website over a ten-week period, without direct instruction After an initial orientation, students independently utilized the platform during designated sessions, receiving technical support from the researcher only when necessary.
The implementation of SVA through a web-based platform involves several key components: an initial listening phase with 15 repetitions of filtered speech, followed by a comprehension quiz to assess understanding of sentence patterns This is succeeded by reinforced listening, which includes 10 additional filtered repetitions, and contrast listening, where students experience 10 repetitions alternating between filtered and unfiltered versions using a dichotic setup Finally, students practice and record sentences for self-assessment, while their activity is tracked to monitor engagement and progress.
The integrated system utilizes Moodle v4.2 for managing access and records, alongside Livresq for delivering audiovisual content This platform encourages focused and autonomous practice of prosody and voiceless consonants, building on established frameworks.
Learners engaged in weekly logs to reflect on their experiences and practice pronunciation, without the use of external materials This approach ensured that the study effectively measured the impact of SVA in a self-contained, independent learning environment while also controlling for extraneous variables.
3.4.2.3 The Role of the Teachers in control and experimental groups
In the control group, the teacher provided direct instruction, guided pronunciation exercises, gave corrective feedback, and monitored homework, playing an active, traditional role
In the experimental group, the teacher served solely as an observer, refraining from providing direct instruction Students participated in independent learning through the website, while the teacher monitored their progress This approach was designed to evaluate the effectiveness of self-directed learning in the absence of teacher intervention.
Research Instruments
A pilot phase was conducted before the main study to identify learner challenges and assess the feasibility of the SVA It informed key refinements:
Pronunciation tests utilized simple vocabulary to minimize cognitive load while maintaining sentence-reading length for thorough assessment In interviews, terms such as "useful" and "effective" were clarified for participants instead of being rephrased Additionally, learner logs were modified based on feedback from both experts and students to better align with research objectives.
These revisions strengthened the study’s validity and ensured all tools effectively captured improvements in voiceless consonant pronunciation
3.5.1 Pronunciation Tests (Pretest and Posttest)
The tests were designed to measure learners' progress in pronunciation before and after the intervention, comparing the effectiveness of each approach The test consisted of three parts:
Part 1: Students read 26 words containing nine voiceless consonants in various positions (beginning, middle, and end) This assessed their ability to pronounce voiceless consonants in isolation Part 2: Students read 104 sentences with these consonants, covering different sentence types (statements, questions, commands, exclamations) to evaluate how well they handled voiceless consonants in varied sentence structures and intonation patterns
Part 3: Students read passages aloud, focusing on intelligibility by incorporating rhythm, stress, and intonation This part assessed how they pronounced voiceless consonants in continuous, natural speech
In this study, only the experimental group participated in the qualitative data collection, aligning with the objective to explore learners' perceptions of the SVA's effectiveness and satisfaction Since only the experimental group experienced the intervention, their insights were deemed most relevant While this approach may seem limiting, it is a widely accepted strategy in intervention-based research aimed at understanding participants' responses to specific treatments (Creswell & Clark, 2017).
Semi-structured interviews were utilized to gather in-depth and meaningful data, combining guided questions with flexible dialogue to enable participants to share their experiences and clarify their thoughts (Ary et al., 2018; Denscombe, 2014) Additionally, weekly learner logs were collected to document reflections throughout the learning process and to track learner engagement.
To ensure the trustworthiness of the qualitative findings, the study followed Lincoln and Guba’s
(1985) criteria: Credibility: through participant checking and the inclusion of direct quotes; Transferability: by providing detailed contextual descriptions; Dependability and Confirmability: through transparent documentation of procedures and researcher neutrality
Open-ended questions were utilized to invite learners to share their genuine opinions on different facets of the SVA, such as its perceived usefulness, enjoyment, and challenges This method not only reduced bias but also provided a deeper understanding of the learning experience.
The researcher utilized Zalo, a widely-used messaging app in Vietnam, to enable learners in the experimental group to document their reflections on the SVA learning process The app's accessibility on smartphones facilitated real-time recording of study habits, challenges, and progress, encouraging frequent, spontaneous, and candid entries.
Learners were prompted to send private logs through direct messages twice a week, documenting their practice times, locations, study durations, and thoughts on the SVA approach This strategy provided a relaxed alternative to interviews, fostering honest self-reflection The researcher kept track of submissions, issued reminders, and offered reflective prompts to improve the quality of entries while maintaining their authenticity.
The logs not only tracked learning behaviors but also captured incidental English exposure from media interactions, which helped control for extraneous variables This additional context enhanced the reliability of the findings concerning pronunciation improvement.
The thematic analysis of logs revealed patterns related to satisfaction, effectiveness, and challenges According to Shek et al (2008), learner logs provide valuable longitudinal insights When integrated with interviews and test data, these logs facilitated data triangulation, enhancing the study's validity and offering a comprehensive perspective on the impact of SVA.
The Pilot Study
The pilot study played a crucial role in enhancing the research tools for both quantitative and qualitative analyses, effectively assessing pronunciation improvements and learner experiences This alignment with the study's mixed epistemology underscores its significance in educational research (Shannon, 2005).
An online registration form was distributed to non-English major students at University “A,” resulting in initial participation from 200 students, who were divided into four groups Participants selected their study times due to practical constraints, following quasi-experimental research practices (Mertens, 2023) Ultimately, 150 students were retained for the study, with Phase 1 (pilot) involving 25 students from Groups 1 and 2, and Phase 2 (main study) including 50 students from Groups 3 and 4 This grouping was designed to control for variables such as age, region, ethnicity, study experience, and prior English exposure, ensuring uniformity among participants.
3.6.2.1 Pre-Test and Post-Test
The Pre-Test and Post-Test, developed from the works of Baker (2006) and O'Connor (1998), specifically target voiceless consonants These tests underwent a thorough content validity review by experts, utilizing the Index of Objective Congruence (IOC) to ensure their effectiveness.
Interviews: Adapted from He and Sangarun (2015), questions evaluated student satisfaction and the effectiveness of the SVA, divided into two clusters for clarity
Expert input was sought before the tests were administered, and participant feedback was gathered after the pre-test to ensure the content was relevant and understandable
3.6.3.1 Pre-test and Post-test
Pre-test and Post-test: Experts found the test appropriate, and participants agreed, though they noted sentence reading length The test length was kept, ensuring a comprehensive pronunciation assessment
Interviews: Retained words like “useful” and “effective” despite participant feedback, with clarifications provided to distinguish their meanings
3.6.4 Results of the Pilot Study
The pilot study confirmed the SVA’s feasibility and validated the research instruments
3.6.4.1 Pre-test and Post-test
Feedback from experts and participants validated the tests' content and structure While participants found the sentence reading section lengthy, it was kept to thoroughly evaluate voiceless consonants in different contexts, ensuring a complete assessment.
The interview questions, adapted from He and Sangarun (2015), centered on the effectiveness and satisfaction with the SVA Although participants expressed confusion over terms such as "useful" and "effective," these terms were preserved due to their unique meanings To enhance understanding, clarifications were provided prior to the main phase of the study.
Pre-Test vs Post-Test Performance Evaluation of Both Groups
The researcher assessed the effectiveness of the pronunciation interventions on both group and individual levels to gain a comprehensive understanding of their impact
Group Level: This analysis identified overall learning patterns by examining collective outcomes
It enabled the researcher to compare the effectiveness of interventions across control and experimental groups
Individual Level: This analysis tracked each student’s progress, capturing unique improvements and differences in learning responses This provided a more detailed understanding beyond group averages
This study examines linguistic focus across three levels: words, sentences, and passages At the word level, learners focus on accurately producing phonemes The sentence level emphasizes sound interactions, including stress, rhythm, and intonation Finally, at the passage level, learners aim for correct pronunciation in extended speech, integrating prosodic features such as pitch and speech flow to enhance intelligibility and coherence in communication.
To assess progress, pre-test and post-test results were evaluated by classifying each pronunciation as "Correct" or "Incorrect." Evaluators listened to recordings and marked the results accordingly This approach facilitated the tracking of student improvement by comparing the number of correct pronunciations before and after the intervention The use of clear criteria reduced bias and maintained consistency, even with multiple evaluators involved.
3.7.1 Performance Evaluation of Voiceless-Sound Word Test
The word reading task employs a straightforward scoring system that categorizes responses as "Correct" or "Incorrect" to evaluate pronunciation Each student is assessed using a score sheet with two columns, one for "Correct" and the other for "Incorrect." The evaluator attentively listens as the student reads 26 words, marking a word as "Correct" if the target sound is pronounced accurately, while any unclear, substituted, or mispronounced sounds are noted as "Incorrect." This method provides a clear and effective means of assessing pronunciation accuracy.
The evaluation of voiceless sound pronunciation during sentence reading focuses on specific phonemes such as /p/, /t/, /k/, /s/, /f/, /θ/, /ʃ/, /ʧ/, and /h/ Instead of assessing the entire sentence, the accuracy of these particular sounds is targeted A simple “Correct” or “Incorrect” system is employed to determine the precision of the phoneme pronunciation A phoneme is marked as “Correct” if pronounced clearly and accurately, while any mispronunciation, omission, or substitution is marked as “Incorrect.”
3.7.3 Performance Evaluation of Voiceless-Sound Passage Test
The researcher created a pronunciation grading scale for the study by adapting criteria from established language proficiency tests like TOEIC, which assesses pronunciation, intonation, fluency, and intelligibility during passage reading Modifying the typical 4-level TOEIC scale to a 5-level scale allowed for finer distinctions in proficiency, particularly for first-year university students The evaluation focused on the accuracy of individual sounds, especially voiceless consonants, and the scoring system was revised to eliminate category overlap, ensuring clear distinctions with a detailed rubric for raters Score ranges were established to reflect pronunciation accuracy levels, from “Intrusive” (0-20) to “Very Good” (81-100), and the revised system was piloted to ensure scoring consistency and reliability.
Procedure for Collecting Data
Step 1: Institutional Approval: The researcher obtained institutional and ethical approvals, ensuring participant protection and informed consent
Step 2: Participant Recruitment: 150 learners were recruited, informed of the study, and consented Step 3: Pilot Phase: A pilot phase tests and refines data collection tools for clarity and effectiveness Step 4: Group Segmentation: Participants were compared between the control and experimental groups Step 5: Baseline Testing: Pre-tests established participants' pronunciation skills for later comparison Step 6: Educational Intervention: The control group used a conventional approach, while the experimental group followed the Simplified Verbotonal Approach
Step 7: Post-Intervention Assessment: Post-tests measured pronunciation improvements in both groups Step 8: Feedback Collection: Feedback from the experimental group was gathered through questionnaires and interviews
Step 9: Comprehensive Data Analysis: Statistical tests and qualitative analysis measured group differences and individual progress.
Data Analysis
Following the intervention, the researcher employed various statistical tests to assess differences within and between the control and experimental groups, utilizing JASP software for both pre-test and post-test evaluations The effectiveness of the Simplified Verbotonal Approach was compared to the conventional method through statistical tests including Mann-Whitney U, Wilcoxon Signed-Rank, Independent Sample T-Test, Paired Sample T-Test, and ANCOVA Descriptive statistics and change score analysis were used to monitor improvements, alongside calculations of growth rates and improvement ratios Furthermore, a questionnaire measured students' perceptions of engagement, confidence, and effectiveness using a Likert scale.
The researcher conducted a thorough analysis of interview and learner log data by identifying key themes and patterns while filtering out irrelevant information This process enabled a deeper interpretation of the interviews' meanings Additionally, the examination of learners' logs provided valuable insights into their experiences, attitudes, and progress, including details like study dates, times, and challenges faced This comprehensive approach revealed both subjective and objective influences that might have been overlooked by other data collection methods, highlighting recurring patterns and unique insights.
Validity and Reliability
3.10.1 Strategies to Enhance Validity and Reliability
A total of 35 students per group were selected using G POWER 3.1 software to ensure accurate and reliable sample sizing (Faul et al., 2013) The statistical significance of the results was determined through t-tests (Cohen et al., 2018).
Pronunciation tests focusing on voiceless consonants were developed using established textbooks, including "Ship or Sheep" and "Better English Pronunciation." The content received validation from three expert lecturers and was evaluated using the "Index of Objective Congruence" (IOC), resulting in a congruence rate exceeding 96%.
Interviews were adapted from He and Sangarun (2015) and Wen (2019), and underwent validation through expert consultation and pilot testing, achieving an IOC score of 88.3% The translations were meticulously verified by bilingual experts and through back-translation methods to ensure accuracy.
To enhance research validity and minimize bias in teaching, instructors responsible for teaching, test scoring, and expert consultation were kept separate Different instructors were assigned to the control and experimental groups to prevent teaching-style biases and methodological cross-contamination The researcher taught the experimental group, while the control group was led by “A,” a highly qualified pronunciation specialist with over ten years of experience and an IELTS speaking score of 8.0, who had no prior relationship with the control group students This strategic separation of roles not only ensured that observed differences were due to instructional interventions but also strengthened the study’s internal validity and the integrity of its findings.
3.10.2 Rater Reliability and Correlation Analysis
In this study, two experienced evaluators conducted blind ratings to assess pronunciation improvements, ensuring impartiality High inter-rater reliability was confirmed with Pearson’s and Spearman’s coefficients exceeding 0.9, indicating strong agreement between the raters Rater 1, a university lecturer with an IELTS speaking score of 8, and Rater 2, a native English lecturer with ten years of teaching experience, both underwent extensive training and calibration sessions to apply consistent scoring criteria The use of human judgment was prioritized over automated tools due to software limitations in accurately reflecting diverse speech patterns and providing detailed feedback Comprehensive training with scoring guidelines and practice sessions further ensured consistent evaluations, while statistical measures confirmed strong alignment in rater evaluations.
Ethical Considerations
Participants were provided with a detailed consent form outlining the study's purpose, procedures, and potential risks, ensuring their voluntary and informed participation Throughout the qualitative phase, confidentiality was upheld by anonymizing the identities of teachers, raters, and experts, with data securely stored in password-protected files Anonymized codes were utilized in reports, and data retention adhered to institutional guidelines In the quantitative phase, student responses and rater feedback were also anonymized, with secure data storage accessible only to the researcher Scores were aggregated to protect confidentiality, safeguard raters from professional risks, and maintain data integrity The study received university approval, ensuring compliance with ethical standards and enhancing its credibility.
AND DISCUSSIONS
Impact on Improving Voiceless-Consonant Pronunciation
This article presents findings from tests that assess the effectiveness of SVA compared to traditional methods in improving learners' accuracy with voiceless consonants It focuses on the comparative improvements at group, individual, and linguistic levels to evaluate the overall impact on enhancing clear and intelligible English pronunciation.
Table 4.1 displays the descriptive statistics for C-GRP and E-GRP regarding pre- and post-test scores for voiceless sounds, categorized into individual voiceless sounds, voiceless-sound sentences, and voiceless-sound passages.
The descriptive statistics indicate that both groups initially performed similarly on voiceless sounds, but the E-GRP exhibited greater variability Post-intervention, the E-GRP consistently surpassed the C-GRP in mean scores across individual sounds, sentence-level, and passage-level assessments While the C-GRP experienced minor improvements or declines, the E-GRP showed significant gains and reduced variability, reflecting more consistent progress These findings suggest that the SVA intervention was effective in enhancing the E-GRP learners' performance on voiceless sounds.
4.1.1.2 Mann-Whitney U Test – Comparison of Independent Samples
The Mann-Whitney U test was chosen for its resilience to normality and variance assumptions, while ANCOVA was utilized for Post-Voiceless Sound Sentences as its assumptions were satisfied Effect sizes were assessed using Rank Biserial Correlation for the Mann-Whitney U test and Cohen’s d for ANCOVA.
Table 4.2: Mann-Whitney U Test (Independent samples test)
Prior to the intervention, the C-GRP and E-GRP exhibited similar performance in tasks involving voiceless sounds, showing only minor and statistically insignificant differences, which indicated that both groups began at a comparable level.
Following the intervention with the SVA, the E-GRP demonstrated significant enhancements across all test types: individual sounds, sentences, and passages Although the improvement in individual voiceless sounds was modest (effect size = 0.22), the advancements were more pronounced in sentences (effect size = 0.93) and passages (effect size = 0.62) These substantial gains indicate that E-GRP learners effectively applied their enhanced perception and articulation of voiceless consonants in longer, more natural speech contexts.
The ANCOVA test demonstrated a significant enhancement in the sentence test while considering initial differences, highlighting the intervention's considerable and measurable effect on learners' pronunciation skills.
Overall, the data highlights that the SVA positively influenced the E-GRP’s ability to perceive and produce voiceless consonants, especially in connected speech, helping them speak more clearly and intelligibly
4.1.1.3 Wilcoxon Signed Rank Test- Comparison of Paired Samples
This section reports improvements in learners’ performance within both C-GRP and E-GRP using the Wilcoxon Signed Rank Test
Table 4.3: Paired Sample Wilcoxon Signed Rank Test – C-GRP
Mean Post – Mean Pre p-value Effect size
The C-GRP results revealed mixed outcomes across various tests The Voiceless Sounds test demonstrated a statistically significant mean increase from 22.26 to 23.00, with a p-value of 0.02 and a moderate effect size of 0.54, indicating a meaningful improvement In contrast, the Voiceless-Sound Sentences test showed a mean increase from 74.26 to 76.69, but with a p-value of 0.07, this change was statistically insignificant, and the small effect size of 0.37 suggested limited impact Additionally, the Voiceless-Sound Passage test experienced a decline in performance, with a mean drop from 62.76 to 60.56, a p-value of 0.73, and a negligible effect size of 0.07, indicating no meaningful effect from the intervention.
The C-GRP demonstrated limited improvement in voiceless sound metrics, but it failed to make significant advancements in sentence-level or passage-level pronunciation, with the latter even experiencing a decline This indicates that traditional treatment methods were ineffective in enhancing pronunciation skills in more complex contexts.
Table 4.4: Paired Sample Wilcoxon Signed Rank Test – E-GRP
E-GRP POST-TEST Mean Post
The E-GRP intervention led to significant improvements in voiceless sound recognition, with mean scores rising from 21.80 to 24.04 (p < 0.001, effect size 0.92) Additionally, voiceless-sound sentences showed a pre-test mean of 67.13 increasing to 79.64 post-test, reflecting a mean difference of 12.51, which was statistically significant (p < 0.001, effect size 1.0) Furthermore, the voiceless-sound passage test demonstrated a pre-test mean score of 65.06, which increased to 72.96 post-test, resulting in a significant mean difference of 7.90 (p < 0.001, effect size 0.97).
The intervention led to a significant enhancement in voiceless sound pronunciation across all assessments, demonstrating large effect sizes and decreased performance variability Notably, the most substantial improvement occurred at the sentence level These findings validate the effectiveness of the SVA in improving pronunciation skills within the E-GRP.
The study demonstrates that E-GRP surpassed C-GRP in voiceless sound pronunciation tasks, validating the Simplified Verbotonal Approach's effectiveness at the group level E-GRP achieved higher mean scores across various sound categories, aligning with previous research on the Traditional Verbotonal Approach (Klein, 2010; He & Sangarun, 2015; Yang, Wannaruk, & Lian, 2017) Notably, this study utilized a self-directed model through a Computer-Based Pronunciation Platform, omitting teacher guidance and gestures Despite the lack of teacher feedback, learners showed significant improvements, suggesting that the SVA is effective in autonomous learning settings These findings resonate with García (2018) and Wen (2019), who acknowledged the TVA's influence on pronunciation while incorporating gestures, which this study excluded The results challenge traditional perspectives by Kendon (1980) and McNeill (1981) regarding the necessity of gestures in language acquisition, indicating that an auditory-focused, self-directed approach can achieve comparable success, making it a viable option for classrooms with limited physical movement.
This section presents individual-level comparisons, offering a detailed analysis of each learner's progress in C-GRP and E-GRP It emphasizes the differences in pronunciation improvement that may be overlooked in group-level data.
Table 4.5: Change Score Analysis of Descriptive Statistics and Mann-Whitney U Test
In the comparison of the “Voiceless Sounds” test, the E-GRP demonstrated a higher mean of 2.43 compared to the C-GRP's 0.74, with a statistically significant p-value of 0.003 and a moderate effect size of 0.42 Similarly, in the “Voiceless Sound Sentences” test, the E-GRP achieved a mean of 12.51, significantly outperforming the C-GRP's 2.43, supported by a p-value of 0.001 and a moderate effect size of 0.58 The "Voiceless Sound Passage" test also revealed that the E-GRP had a mean of 7.90, significantly exceeding the C-GRP’s mean of -2.20, with a p-value of 0.001 and an effect size of 0.48 Overall, the E-GRP consistently outperformed the C-GRP across all tests, indicating significant improvements and moderate practical significance, particularly in complex sentence and passage tasks, thereby confirming the intervention’s effectiveness in enhancing voiceless sound production.
The Change Score Analysis Breakdown offers a detailed examination of learners' performance variations—highlighting improvements, declines, and stability—throughout the study, enabling an accurate evaluation of SVA's influence.
Table 4.6: Change Score Analysis Breakdown
Test Voiceless Sounds Voiceless-Sound
C-CRP E-GRP C-GRP E-GRP C-GRP E-GRP
Regression:The C-GRP showed regression in all tests, ranging from -9 learners (Voiceless sounds) to -14 learners (Voiceless-Sound Passage), while the E-GRP showed very small learner regressions (-2 to -3).
The Learners’ Opinions on Using SVA
The following section presents interview findings providing insights into learners’ opinions on SVA and its impact on pronunciation improvement
This section presents the results of a semi-structured interview aimed at obtaining detailed insights from the experimental group about their satisfaction and the effectiveness of the SVA in improving pronunciation.
4.2.1.1 Learner Satisfaction with the Simplified Verbotonal Approach
The study revealed that learners valued the SVA for its innovative and engaging approach to improving pronunciation, leading to increased motivation, confidence, and awareness of pronunciation errors Participants particularly enjoyed the self-directed learning style, with a focus on prosody, intonation, and filtered sentence exercises that enhanced their ability to distinguish and produce voiceless sounds Many reported significant improvements in articulating final consonants and consonant clusters, contributing to better intelligibility and a more natural speech rhythm However, a minority of learners experienced frustration, feeling they made little to no progress or even regressed in their pronunciation skills, indicating that SVA may not cater to all learning styles, especially for those who thrive on direct feedback and structured guidance from teachers.
The SVA is an innovative tool that enhances interest, self-awareness, and speech clarity for many learners However, some students may require additional support to effectively translate improved listening skills into accurate spoken output This underscores the need for flexibility and a learner-centered approach in pronunciation instruction.
4.2.1.2 Effectiveness of the Simplified Verbotonal Approach
The study reveals that the SVA significantly enhances learners' pronunciation and speech intelligibility, with over 85% of participants reporting increased confidence and clearer speech They gained a better understanding of sound production and connections, especially through filtered auditory input and intonation-focused exercises Participants valued the natural rhythm and flow of speech fostered by this approach, resulting in improved performance in pronunciation tasks, particularly at the sentence and passage levels.
The findings indicate that not all learners experienced equal benefits from the program, with some reporting no significant improvement and others experiencing a regression in pronunciation These learners faced challenges due to the lack of explicit articulation instruction and real-time feedback, particularly with voiceless consonants not present in their first language They expressed a need for enhanced visual support, step-by-step guidance, and greater teacher involvement While SVA improves prosodic awareness, it may not adequately address the needs of students requiring structured, segmental-focused training Additionally, learners suggested enhancements for the SVA platform, including features to compare their voices with native speakers, IPA transcriptions, interactive visuals, adaptive quizzes, and progress-tracking tools, reflecting a desire for a more dynamic and personalized learning experience.
The SVA is effective for enhancing prosody and pronunciation in many learners, but it is not universally applicable To optimize its effectiveness, it should be supplemented with explicit phonetic instruction, visual aids, interactive feedback, and teacher support, allowing learners with varying needs to attain fluency and accurate pronunciation.
4.2.1.3 The Discussion on Findings from Interviews Using SVA
This discussion offers a structured analysis of learners’ opinions on the satisfaction and effectiveness of the SVA, as detailed below:
The interview results indicate that the SVA significantly enhanced learner engagement, confidence, and satisfaction, which are crucial for effective pronunciation improvement Students found the SVA to be more interactive and enjoyable compared to traditional methods, with its novelty helping to maintain focus and motivation, supporting Gardner’s (2007) assertion that engaging activities boost learner motivation This heightened engagement resulted in increased confidence, as many participants felt more at ease speaking and more in control of their learning, reflecting Bandura’s (1977) Self-Efficacy Theory The low-pressure environment of the SVA also alleviated the fear of making mistakes, aligning with Horwitz et al.’s (1986) Foreign Language Anxiety Theory, which emphasizes the need to reduce anxiety in language learning Additionally, learners reported high satisfaction, appreciating that the SVA accommodated their learning styles through a self-paced, learner-centered approach, allowing improvement without the stress of public speaking or strict corrections, consistent with Baran-Lucarz’s (2014) findings on pronunciation anxiety and the importance of a comfortable learning environment.
SVA fostered a motivating and supportive atmosphere through engaging tasks, self-study opportunities, and a focus on reducing anxiety This approach resulted in increased effort, persistence, and improvement in pronunciation skills The findings align with Gardner’s (2007) motivation model, indicating that learners are more likely to achieve success when they experience interest, confidence, and satisfaction.
The interview results indicate that the SVA significantly enhanced learners' pronunciation of voiceless consonants by fostering engagement, self-awareness, and consistent practice Most learners found the web-based platform beneficial, particularly valuing the structured five-step process that included filtered listening, comparison exercises, and repeated practice Notably, activities like dichotic listening were instrumental in helping learners internalize challenging voiceless sounds, thereby boosting their accuracy and confidence in speech, in line with Bandura’s Self-Efficacy Theory.
(1977) and Gardner’s Motivation Theory (2007) Many learners reported better fluency, more precise articulation, and reduced anxiety, particularly because the approach minimized pressure and allowed for independent learning
Not all learners benefited equally from the SVA approach; some struggled with specific sounds such as /θ/, /ʧ/, and aspirated stops like /p/ and /k/, leading to feelings of confusion and frustration These learners expressed a need for explicit articulation guidance and real-time feedback, which the current SVA model does not provide Instead of direct correction, SVA encourages self-correction through auditory perception, a method that some found uncertain and ineffective without teacher support This aligns with the findings of Nguyen et al (2021) and Zielinski & Yates (2014), highlighting the importance of explicit phonetic instruction and structured, teacher-led feedback for many learners.
While most learners showed improvement, some did not progress or even regressed, likely due to an overemphasis on prosody at the cost of segmental clarity This limitation of SVA suggests that its perception-based approach may not adequately support learners needing detailed guidance for unfamiliar sounds These findings align with McCrocklin (2019), who emphasized that pronunciation tools are more effective when they offer explicit feedback and bolster learner confidence through precise corrections.
SVA significantly enhances pronunciation skills, encourages self-study, and boosts motivation among students by alleviating anxiety and improving prosodic awareness To maximize its effectiveness, SVA should integrate visual articulation guides, provide real-time corrective feedback, and increase teacher involvement, particularly for learners who thrive on explicit instruction These enhancements would create a more inclusive and effective learning environment that caters to diverse learner needs.
Student logs provide valuable data on peer engagement and feedback processes, offering real-time insights while effectively managing external factors like additional English exposure This approach allows for a clear assessment of the SVA's impact on pronunciation enhancements.
Logs and interviews indicate that most learners aimed to reduce distractions from external influences such as music or foreign films to concentrate on the SVA However, individual motivation levels significantly impacted their progress, with some learners intentionally restricting their exposure to English media to enhance their focus.
The effectiveness of SVA is influenced by learner motivation, with highly motivated individuals demonstrating deeper engagement and greater progress Conversely, some learners struggle with the unfamiliar SVA style, indicating that ongoing support and monitoring of motivation and engagement are essential for maximizing the benefits of SVA.
Evolution from Traditional to Simplified Model
The study demonstrates that the SVA significantly enhances learners' pronunciation of voiceless consonants, especially at the sentence and passage levels Participants in the E-GRP, who utilized the SVA, achieved higher mean scores and greater intelligibility compared to those in the C-GRP This supports the effectiveness of a prosody-first, top-down approach, as advocated by Gilbert (2008) and Jackson & O’Brien (2011), which prioritizes rhythm, intonation, and stress before focusing on individual phonemes.
The SVA promotes learner self-study and perception-driven practice through tools like filtered sentence exercises and a self-study platform, rather than relying on body movement or direct teacher guidance This approach enhances accessibility and flexibility in modern classrooms, enabling learners to internalize sound patterns and self-correct via repeated exposure Filtering techniques increase awareness of voiceless sounds in natural speech, leading to improved pronunciation accuracy and fluency These insights build on previous TVA research, demonstrating that prosody-based training is effective for voiced sounds and can be adapted for challenging voiceless consonants, particularly for Vietnamese learners.
Both quantitative and qualitative data support the effectiveness of SVA, with learners reporting high satisfaction, motivation, and confidence, aligning with Gardner’s motivation theory and Bandura’s self-efficacy framework Engagement and self-awareness, as highlighted in learner logs and interviews, led to significant improvements in connected speech and communication However, the study identifies limitations, noting that while SVA effectively enhances sentence- and passage-level fluency, it falls short at the isolated word level Some learners faced challenges in articulating voiceless phonemes like /θ/ and /tʃ/ due to insufficient explicit articulation instruction This indicates a need for supplemental segmental-focused training, particularly for those who benefit from structured phonetic guidance The findings are consistent with Nguyen et al (2021) and Zielinski & Yates (2014), who noted that clear corrective feedback and articulation modeling are essential for accurate pronunciation improvement.
The SVA is an innovative and research-supported framework for teaching pronunciation that improves learners' intelligibility by focusing on prosody and perception It promotes motivation, autonomy, and fluency, but should be complemented with explicit articulation techniques to meet the diverse needs of all learners, particularly those who thrive with traditional phonetic instruction.
The SVA is a contemporary and efficient framework for teaching pronunciation, though it may need additional methods to overcome certain limitations This model emphasizes a streamlined approach, utilizing prosody and digital tools to enhance clarity, fluency, and overall speech intelligibility, as illustrated in Figure 4.6.
Figure 4.6: The Study’s Final Model