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they think of it as a very slow process Question 4: According to the passage, agriculture furthers desertification through which of the following activities A.. consumption Question 6:

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DESERTIFICATION Desertification is the degradation of once-productive land into unproductive or poorly

productive land Since the first great urban-agricultural centers in Mesopotamia nearly 6,000 years ago, human activity has had a destructive impact on soil quality, leading to gradual desertification in

virtually every area of the world

It is a common misconception that desertification is caused by droughts Although drought does make land more vulnerable, well-managed land can survive droughts and recover, even in arid regions Another mistaken belief is that the process occurs only along the edges of deserts In fact, it may take place in any arid or semiarid region, especially where poor land management is

practiced Most vulnerable, however, are the transitional zones between deserts and arable land; wherever human activity leads to land abuse in these fragile marginal areas, soil destruction is inevitable

[1] Agriculture and overgrazing are the two major sources of desertification [2] Large-scale farming requires extensive irrigation, which ultimately destroys lands by depleting its nutrients and leaching minerals into the topsoil [3] Grazing is especially destructive to land because,

in addition to depleting cover vegetation, herds of grazing mammals also trample the fine organic particles of the topsoil, leading to soil compaction and

erosion [4] It takes about 500 years for the earth to build up 3 centimeters of topsoil However, cattle ranching and agriculture can deplete as much as 2 to 3 centimeters of topsoil every 25 years - 60 to 80 times faster than it can be replaced by nature

Salination is a type of land degradation that involves an increase in the salt content of

the soil This usually occurs as a result of improper irrigation practices The greatest Mesopotamian empires- Sumer, Akkad and Babylon- were built on the surplus of the enormously productive soil of the ancient Tigris- Euphrates alluvial plain After nearly a thousand years of intensive cultivation, land quality was in evident decline In response, around 2800 BC the Sumerians began digging the huge Tigris-Euphrates canal system to irrigate the exhausted soil A temporary gain in crop yield was achieved in this way, but over-irrigation was to have serious and unforeseen consequences From as early as 2400 BC we find Sumerian documents referring to salinization as a soil problem It is believed that the fall of the Akkadian Empire around 2150 BC may have been due to a catastrophic failure in land productivity; the soil was literally turned into salt Even today, four thousand years later, vast tracks of salinized land between the Tigris and Euphrates rivers still resemble rock-hard fields of snow

Soil erosion is another form of desertification It is a self-reinforcing process; once the cycle of degradation begins, conditions are set for continual deterioration As the vegetative cover begins to disappear, soil becomes more vulnerable to raindrop impact Water runs off instead of soaking

in to provide moisture for plans This further diminishes plan cover by leaching away nutrients from

the soil As soil quality declines and runoff is increased, floods become more frequent and more severe Flooding washes away topsoil, the thin, rich, uppermost layer of the earth’s soil, and leaves finer underlying particles more vulnerable to wind erosion Topsoil contains the earth’s greatest

concentration of organic matter and microorganisms, and is where most of the earth’s land-based biological activity occurs Without this fragile coat of nutrient-laden material, plan life cannot exist

An extreme case of its erosion is found in the Sahel, a transitional zone between the Sahara Desert and the tropical African rain forests; home to some 56 million people Overpopulation and

overgrazing have opened the hyperarid land to wind erosion, which is stripping away the

protective margin of the Sahel, and causing the desert to grow at an alarming rate Between

1950 and 1975, the Sahara Desert spread 100 kilometers southward through the Sahel

Question 1: Which of the following statement is true about desertification?

A It has a history as long as that of civilization.

B It was just as serious in the past as it is today.

C It is a fairy recent problem.

D Ancient societies managed the problem well.

Question 2: The word “arable” in paragraph 2 is closet in meaning to _.

Question 3: According to the passage, many people’s understanding of desertification is incorrect

because _

A they do not think of of it as a serious problem

B they see it as being reversible

C they do not see it as being caused by human activity

D they think of it as a very slow process

Question 4: According to the passage, agriculture furthers desertification through which of the

following activities

A The repetitive planting of the same crop B Irrigation

C The stripping away of native vegetation D Over fertilization

Question 5: The word “degradation” in paragraph 4 is closet in meaning to _.

A rejuvenation B deterioration C contribution D consumption

Question 6: Paragraph 4 of the passage serves mainly to do which of the following?

A Show the progress of desertification down through history.

B Propose a method for dealing with the desertification problem.

C Describe one progress that leads to desertification

D Describe the main cause of desertification in one particular area

Question 7: The word “leaching” in paragraph 5 is closet in meaning to _.

A washing B depositing C concentrating D dispersing

(1) Iron production was revolutionized in the early eighteenth century when coke was first used instead of charcoal for refining iron ore Previously the poor quality of the iron had restricted its use in architecture to items such as chains and tie bars for supporting arches, vaults, and walls With the improvement in refining ore, it was now possible to make cast-iron beams, columns, and girders During the nineteenth century further advances were made, notably Bessemer’s process for

converting iron into steel, which made the material more commercially viable

(2) Iron was rapidly adopted for the construction of bridges, because its strength was far greater than that of stone or timber, but its use in the architecture of buildings developed more slowly By 1800 a complete internal iron skeleton for buildings had been developed in industrial architecture replacing traditional timber beams, but it generally remained concealed Apart from its low cost, the appeal of iron as a building material lay in its strength, its resistance to fire, and its

potential to span vast areas As a result, iron became increasingly popular as a structural material for more traditional styles of architecture during the nineteenth century, but it was invariably concealed

(3) Significantly, the use of exposed iron occurred mainly in the new building types spawned by the Industrial Revolution: in factories, warehouses, commercial offices, exhibition hall, and railroad stations, where its practical advantages far outweighed its lack of status Designers

of the railroad stations of the new age explored the potential of iron, covering huge areas with spans that surpassed the great vaults of medieval churches and cathedrals Paxton’s Crystal Palace, designed to house the Great Exhibition of 1851, covered an area of 1.848 feet by 408 feet in

prefabricated units of glass set in iron frames The Paris Exhibition of 1889 included both the widest span and the greatest height achieved so far with the Halle Des Machines, spanning 362 feet, and the Eiffel Tower 1,000 feet high However, these achievements were mocked by the artistic elite of Paris as expensive and ugly follies Iron, despite its structural advantages, had little aesthetic status The use of

an exposed iron structure in the more traditional styles of architecture was slower to develop

Question 8: What does the passage mainly discuss?

A Advances in iron processing in the eighteenth and nineteenth centuries.

B The effects of the Industrial Revolution on traditional architectural styles.

C Advantages of stone and timber over steel as a building material.

D The evolution of the use of iron in architecture during the 1800’s.

Question 9: According to the passage, iron was NOT used for beams, columns, and girders prior to the

early eighteenth century because _

A all available iron was needed for other purposes

B limited mining capability made iron too expensive

C iron was considered too valuable for use in public buildings

D the use of charcoal for refining ore produced poor quality iron

Question 10: Iron replaced stone and timber in the building of bridges because iron was considered

_

A more beautiful B new and modern C much stronger D easier to transport

Question 11: The word “it” in paragraph 2 refers to _.

A industrial architecture B internal iron skeleton

Question 12: The word “surpassed” is closest in meaning to _.

Question 13: According to paragraph 3, the architectural significance of the Halle Des Machines was

its _

A wide span B great height

C unequaled beauty D prefabricated unites of glass

Question 14: How did the artistic elite mentioned in the passage react to the buildings at the Paris

Exhibition?

A They tried to copy them B They ridiculed them.

C They praised them D They refused to pay to see them.

Question 15: It can be inferred that the delayed use of exposed iron structures in traditional

styles of architecture is best explained by the _

A impracticality of using iron for small, noncommercial buildings

B association of iron architecture with the problems of the Industrial Revolution

C general belief that iron offered less resistance to fire and harsh weather than traditional materials

D general perception that iron structures were not aesthetically pleasing

(1) Interest is the sum charged for borrowing money for a fixed period of time Principal is the term

used for the money that is borrowed, and the rate of interest is the percent per year of the principal

charged for its use Most of the profits for a bank are derived from the interest that they charge for the

use of their own or their depositor’s money

(2) All problems in interest may be solved by using one general equation that may be stated as follows:

Interest = Principal X Rate X Time (3) Any one of the four quantities – that is, interest, principal, rate, or time – may be found when the other three are known The time is expressed in years The rate is expressed as a decimal fraction Thus,

6 percent interest means six cents charged for the use of $1 of principal borrowed for one year

Although the time may be less than, equal to, or greater than one year, most applications for loans are

for periods of less than one year For purpose of computing interest for short periods, the commercial

year or 360 days is commonly used, but when large sums of money are involved, exact interest is computed on the basis of 365 days

Question 16: With what topic is this passage primarily concerned?

Question 17: The word “fixed” in paragraph 1 is closest in meaning to

Question 18: At 4 percent interest for the use of $1 principal, how much would one pay?

(A) Six cents per year (B) Twenty-five cents per year

(C) Four cents per year (D) One cent per year

Question 19: Which of the following would be a correct expression of an interest rate as stated in the

equation for computing interest?

(A) Four (B) 04 (C) 4 (D) 4/100

Question 20: Most applications for loans are for

(A) one year (B) less than one year (C) more than one year (D) 360 days

Question 21: The word “periods” in paragraph 3 refers to

Question 22: A commercial year is used to compute

(A) exact interest (B) interest on large sums of money

(C) interest on a large principal (D) interest for short periods of time

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm,

constitute a classification of the most primitive forms of animal life They are fantastically diverse, but three major groups may be identified on the basis of their motility The Mastigophora have one or more long tails, which they use to project themselves forward The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies

(2) In addition to their form of movement, several other features discriminate among the three groups

of protozoans For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that

contains the genetic code necessary to generate the large nucleus

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are

otherwise almost identical, they do not live on simple organic compounds Their cell demonstrates all

of the major characteristics of the cells of higher animals

(4) Many species of protozoans collect into colonies, physically connected to each other and

responding uniformly to outside stimulate Current research into this phenomenon, along with

investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified No doubt, as the technology improves our methods of observation, better models of classification will be proposed

Question 23: Where do protozoans probably live?

Question 24: What is protoplasm?

(A) A class of protozoan

(B) The substance that forms the cell of a protozoan

(C) A primitive animal similar to a protozoan

(D) An animal that developed from a protozoan

Question 25: To which class of protozoans do the amoebae belong?

(A) Mastigophora (B) Ciliata (C) Sarcodina (D) Motility

Question 26: What is the purpose of the large nucleus in the Ciliata?

(A) It generates the other nucleus

(B) It contains the genetic code for the small nucleus

(C) It regulates growth

(D) It reproduces itself

Question 27: Why are protozoans classified as animals?

(A) They do not live on simple organic compounds

(B) They collect in colonies

(C) They respond uniformly to outside stimulate

(D) They may have more than one cell

Question 28: The word “uniformly” in paragraph 4 is closest in meaning to

(A) in the same way (B) once in a while (C) all of a sudden (D) in the long run

Question 29: The word “they” in paragraph 3 refers to

(A) protozoans (B) microscopes (C) investigations (D) colonies

Question 30: Which of the following statements are NOT true of protozoans?

(A) There are approximately 40,000 species

(B) They are the most primitive forms of animal life

(C) They have a large cell and a smaller cell

(D) They are difficult to observe

Reading to oneself is a modern activity which was almost unknown to the scholars of the classical and medieval worlds, while during the fifteenth century the term “reading” undoubtedly meant reading

aloud Only during the nineteenth century did silent reading become commonplace

One should be wary, however, of assuming that silent reading came about simply because reading aloud was a distraction to others Examinations of factors related to the historical development of silent reading have revealed that it became the usual mode of reading for most adults mainly because the tasks themselves changed in character

The last century saw a steady gradual increase in literacy and thus in the number of readers As the number of readers increased, the number of potential listeners declined and thus there was some reduction in the need to read aloud As reading for the benefit of listeners grew less common, so came the flourishing of reading as a private activity in such public places as libraries, railway carriages and offices, where reading aloud would cause distraction to other readers

Towards the end of the century, there was still considerable argument over whether books should be used for information or treated respectfully and over whether the reading of materials such as

newspapers was in some way mentally weakening Indeed, this argument remains with us still in education However, whatever its virtues, the old shared literacy culture had gone and was replaced by

the printed mass media on the one hand and by books and periodicals for a specialised readership on

the other

By the end of the twentieth century, students were being recommended to adopt attitudes to books

and to use reading skills which were inappropriate, if not impossible, for the oral reader The social,

cultural and technological changes in the century had greatly altered what the term “reading” implied

Câu 31: Reading aloud was more common in the medieval world because

A few people could read to themselves

B there were few places available for private reading

C silent reading had not been discovered

D people relied on reading for entertainment

Câu 32: The word “commonplace” in the first paragraph mostly means “ _ ”

A attracting attention B for everybody’s use C most preferable D widely used

Câu 33: The development of silent reading during the last century indicated

A an increase in the number of books B an increase in the average age of readers

C a change in the status of literate people D a change in the nature of reading

Câu 34: Silent reading, especially in public places, flourished mainly because of _

A the decreasing need to read aloud B the development of libraries

C the increase in literacy D the decreasing number of listeners

Câu 35: It can be inferred that the emergence of the mass media and specialised reading materials was

an indication of _

A a decline of standards of literacy B a change in the readers’ interest

C an improvement of printing techniques D an alteration in educationalists’ attitudes

Câu 36: The phrase “a specialised readership” in paragraph 4 mostly means “ ”

A a status for readers specialised in mass media

B a limited number of readers in a particular area of knowledge

C a requirement for readers in a particular area of knowledge

D a reading volume for particular professionals

Câu 37: All of the following might be the factors that affected the continuation of the old shared

literacy culture EXCEPT

A the inappropriate reading skills B the printed mass media

C the diversity of reading materials D the specialised readership

The Sun today is a yellow dwarf star It is fueled by thermonuclear reactions near its center that convert hydrogen to helium The Sun has existed in its present state for about four billion six hundred million years and is thousands of times larger than the Earth

By studying other stars, astronomers can predict what the rest of the Sun’s life will be like About five billion years from now, the core of the Sun will shrink and become hotter The surface temperature will fall The higher temperature of the center will increase the rate of thermonuclear reactions The outer regions of the Sun will expand approximately 35 million miles, about the distance to Mercury, which is the closest planet to the Sun The Sun will then be a red giant star Temperatures on the Earth will become too high for life to exist

Once the Sun has used up its thermonuclear energy as a red giant, it will begin to shrink After it shrinks to the size of the Earth, it will become a white dwarf star The Sun may throw off huge amounts

of gases in violent eruptions called nova explosions as it changes from a red giant to a white dwarf After billions of years as a white dwarf, the Sun will have used up all its fuel and will have lost its heat Such a star is called a black dwarf After the Sun has become a black dwarf, the Earth will be dark

and cold If any atmosphere remains there, it will have frozen over the Earth’s surface

Câu 38: It can be inferred from the passage that the Sun _

A has been in existence for 10 billion years

B is approximately halfway through its life as a yellow dwarf

C will continue to be a yellow dwarf for another 10 billion years

D is rapidly changing in size and brightness

Câu 39: When the Sun becomes a red giant, what will the atmosphere be like on the Earth?

A It will become too hot for life to exist

B It will be enveloped in the expanding surface of the sun

C It will freeze and become solid

D It will be almost destroyed by nova explosions

Câu 40: Large amounts of gases may be released from the Sun at the end of its life as a

A white dwarf B red giant C yellow dwarf D black dwarf

Câu 41: As a white dwarf, the Sun will be _

A a cool and habitable planet B the same size as the planet Mercury

C thousands of times smaller than it is today D around 35 million miles in diameter

Câu 42: The Sun will become a black dwarf when _

A the outer regions of the Sun expand B it has used up all its fuel as a white dwarf

C the Sun moves nearer to the Earth D the core of the Sun becomes hotter

Câu 43: The word “there” in the last sentence of paragraph 4 refers to

C the outer surface of the Sun D the planet Mercury Câu 44: This passage is intended to _

A describe the changes that the Sun will go through

B discuss conditions on the Earth in the far future

C alert people to the dangers posed by the Sun

D present a theory about red giant stars

Câu 45: The passage has probably been taken from _

A a scientific chronicle B a news report

C a work of science fiction D a scientific journal