Tài liệu ngữ pháp tiếng anh present perfect since and for

Tài liệu ngữ pháp tiếng anh tham khảo - Present Perfect- since and for

Present Perfect:

Since and For

Bill Gates and

Microsoft

6

Who Is Bill Gates?

Bill Gates is one of the richest and most

successful business executives in the world

Millions of people have used his computer

programs for the past three decades

Bill Gates has always loved working with

computers In fact, he has programmed

computers since his early teens

He has been the CEO of Microsoft Corporation since 1975 Since then, Bill Gates has written several books and has given billions of dollars to schools For the last several years, he and his wife Melinda have donated a substanial amount

of money to organizations working in global

health

Form 1

The present perfect is formed with:

Bill Gates has been has been the CEO since 1975.

Many people have used have used Microsoft’s programs.

+

form of

have

past participle

Form 2

Form 2

Past participles can be regular or regular irregular irregular

Gates has always loved loved

working with computers.

The regular form of the past participle is

base form of verb + -d or -ed.

The regular form of the past participle is

base form of verb + -d or -ed.

Gates has been has been the CEO since 1975.

He and his wife have given have given lots of money to schools.

Form 3

There are many

irregular past participles.

There are many irregular past participles

Past participles can be regular or irregular.

Form 4

Note these common irregular past participles common irregular past participles

write – written give – given

be – been see – seen read – read do

– done

Bill Gates has been CEO of Microsoft since 1975.

Present Perfect

Use the present perfect to talk about something that

began in the past and continues into the present (and

may continue into the future)

future

1975

past

now

since 1975

has been CEO

Bill Gates has written several books since 1975.

Using Since 1

Use the present perfect with since + point in time

to show when something started

future

1975

past

now

since 1975.

has written several books

Gates has programmed computers since he was 13 years old.

Using Since 2

Since can also introduce a time clause

future

age 13

past

now since he was 13 years old.

time clause

Change the sentences to present perfect Add the since phrase in parentheses and delete any past tense time phrases.

Maria was in the garden yesterday ( since 9 a.m.)

Practice 1

Maria has been in the garden since 9 a.m.

Maria has been in the garden since 9 a.m.

1 Bill Gates wrote many emails yesterday ( since 1975)

2 They gave a lot of books to schools last year ( since 1990)

3 I saw many friends last weekend ( since I came home)

4 My sister read many articles last night ( since last August)

5 My friend worked at a pizza place a year ago ( since 2003)

Example:

Bill Gates has written many emails since 1975.

Bill Gates has written many emails since 1975.

They have given a lot of books to schools since 1990 They have given a lot of books to schools since 1990.

I have seen many friends since I came home.

I have seen many friends since I came home.

My sister has read many articles since last August.

My sister has read many articles since last August.

My friend has worked at a pizza place since 2003.

My friend has worked at a pizza place since 2003.

Millions of people have used Gates’s

software for the last three decades.

Using For

Use for + length of time to show how long

something has lasted

future past

now for the last three decades

have used Gates’s software

for three decades

Since and For

Note the difference between since and since for for

five o’clock

yesterday

last summer

1996

he was a child

time

ten minutes two days three decades many years

a long time

Complete the sentences with

since or for.

Bill Gates has been married to Melinda

French Gates _ 1994

Practice 2

1 Computers have been used in schools more

than a decade

2 I have had a computer in my office the

mid-1990s

3 Many students have worked with computers

many years

4 My computer hasn’t given me any problems

last year

Example:

since

for since

for since

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