Monday 11 February 2013

Units 4 & 5 Present Perfect (vs Past Simple)

Present Perfect

FORM

[has/have + past participle]
Examples:
  • You have seen that movie many times.
  • Have you seen that movie many times?
  • You have not seen that movie many times.
Complete List of Present Perfect Forms

USE 1 Unspecified Time Before Now


We use the Present Perfect to say that an action happened at an unspecified time before now. The exact time is not important. You CANNOT use the Present Perfect with specific time expressions such as: yesterday, one year ago, last week, when I was a child, when I lived in Japan, at that moment, that day, one day, etc. We CAN use the Present Perfect with unspecific expressions such as: ever, never, once, many times, several times, before, so far, already, yet, etc.
Examples:
  • I have seen that movie twenty times.
  • I think I have met him once before.
  • There have been many earthquakes in California.
  • People have traveled to the Moon.
  • People have not traveled to Mars.
  • Have you read the book yet?
  • Nobody has ever climbed that mountain.
  • A: Has there ever been a war in the United States?
    B: Yes, there has been a war in the United States.

How Do You Actually Use the Present Perfect?

The concept of "unspecified time" can be very confusing to English learners. It is best to associate Present Perfect with the following topics:

TOPIC 1 Experience

You can use the Present Perfect to describe your experience. It is like saying, "I have the experience of..." You can also use this tense to say that you have never had a certain experience. The Present Perfect is NOT used to describe a specific event.
Examples:
  • I have been to France.
    This sentence means that you have had the experience of being in France. Maybe you have been there once, or several times.
  • I have been to France three times.
    You can add the number of times at the end of the sentence.
  • I have never been to France.
    This sentence means that you have not had the experience of going to France.
  • I think I have seen that movie before.
  • He has never traveled by train.
  • Joan has studied two foreign languages.
  • A: Have you ever met him?
    B: No, I have not met him.

TOPIC 2 Change Over Time

We often use the Present Perfect to talk about change that has happened over a period of time.
Examples:
  • You have grown since the last time I saw you.
  • The government has become more interested in arts education.
  • Japanese has become one of the most popular courses at the university since the Asian studies program was established.
  • My English has really improved since I moved to Australia.

TOPIC 3 Accomplishments

We often use the Present Perfect to list the accomplishments of individuals and humanity. You cannot mention a specific time.
Examples:
  • Man has walked on the Moon.
  • Our son has learned how to read.
  • Doctors have cured many deadly diseases.
  • Scientists have split the atom.

TOPIC 4 An Uncompleted Action You Are Expecting

We often use the Present Perfect to say that an action which we expected has not happened. Using the Present Perfect suggests that we are still waiting for the action to happen.
Examples:
  • James has not finished his homework yet.
  • Susan hasn't mastered Japanese, but she can communicate.
  • Bill has still not arrived.
  • The rain hasn't stopped.

TOPIC 5 Multiple Actions at Different Times

We also use the Present Perfect to talk about several different actions which have occurred in the past at different times. Present Perfect suggests the process is not complete and more actions are possible.
Examples:
  • The army has attacked that city five times.
  • I have had four quizzes and five tests so far this semester.
  • We have had many major problems while working on this project.
  • She has talked to several specialists about her problem, but nobody knows why she is sick.

Time Expressions with Present Perfect

When we use the Present Perfect it means that something has happened at some point in our lives before now. Remember, the exact time the action happened is not important.

Sometimes, we want to limit the time we are looking in for an experience. We can do this with expressions such as: in the last week, in the last year, this week, this month, so far, up to now, etc.

Examples:
  • Have you been to Mexico in the last year?
  • I have seen that movie six times in the last month.
  • They have had three tests in the last week.
  • She graduated from university less than three years ago. She has worked for three different companies so far.
  • My car has broken down three times this week.

NOTICE

"Last year" and "in the last year" are very different in meaning. "Last year" means the year before now, and it is considered a specific time which requires Simple Past. "In the last year" means from 365 days ago until now. It is not considered a specific time, so it requires Present Perfect.
Examples:
  • I went to Mexico last year.
    I went to Mexico in the calendar year before this one.
  • I have been to Mexico in the last year.
    I have been to Mexico at least once at some point between 365 days ago and now.

USE 2 Duration From the Past Until Now (Non-Continuous Verbs)


With Non-Continuous Verbs and non-continuous uses of Mixed Verbs, we use the Present Perfect to show that something started in the past and has continued up until now. "For five minutes," "for two weeks," and "since Tuesday" are all durations which can be used with the Present Perfect.
Examples:
  • I have had a cold for two weeks.
  • She has been in England for six months.
  • Mary has loved chocolate since she was a little girl.
Although the above use of Present Perfect is normally limited to Non-Continuous Verbs and non-continuous uses of Mixed Verbs, the words "live," "work," "teach," and "study" are sometimes used in this way even though they are NOT Non-Continuous Verbs.

ADVERB PLACEMENT

The examples below show the placement for grammar adverbs such as: always, only, never, ever, still, just, etc.
Examples:
  • You have only seen that movie one time.
  • Have you only seen that movie one time?

ACTIVE / PASSIVE

Examples:
  • Many tourists have visited that castle. Active
  • That castle has been visited by many tourists. Passive
More About Active / Passive Forms

EXERCISES AND RELATED TOPICS






PRESENT PERCFECT vs PAST SIMPLE

Simple Past Present Perfect Simple
irregular verbs: see 2nd column of irregular verbs
Example:
I spoke
irregular verbs: form of 'have' + 3rd column of irregular verbs
Example:
I / you / we / they have spoken
he / she / it has spoken
regular verbs: infinitive + ed
Example:
I worked
regular verbs: form of 'have' + infinitive + ed
Example:
I / you / we / they have worked
he / she / it has worked
Exceptions
Exceptions when adding 'ed':
  • when the final letter is e, only add d
    Example:
    love - loved
  • after a short, stressed vowel, the final consonant is doubled
    Example:
    admit - admitted
  • final l is always doubled in British English (not in American English)
    Example:
    travel - travelled
  • after a consonant, final y becomes i (but: not after a vowel)
    Example:
    worry - worried
    but: play - played
See also explanations on Simple Past and Present Perfect Simple

Use

In British English, the use of Simple Past and Present Perfect is quite strict. As soon as a time expression in the past is given, you have to use Simple Past. If there are no signal words, you must decide if we just talk about an action in the past or if its consequence in the present is important.
Note that the following explanations and exercises refer to British English only. In American English, you can normally use Simple Past instead of Present Perfect. We cannot accept this in our exercises, however, as this would lead to confusions amongst those who have to learn the differences.

Certain time in the past or just / already / yet?

Do you want to express that an action happened at a certain time in the past (even if it was just a few seconds ago) or that an action has just / already / not yet happened?
Simple Past Present Perfect Simple
certain time in the past
Example:
I phoned Mary 2 minutes ago.
just / already / not yet
Example:
I have just phoned Mary.

Certain event in the past or how often so far?

Do you want to express when a certain action took place or whether / how often an action has happened till now?
Simple Past Present Perfect Simple
certain event in the past
Example:
He went to Canada last summer.
whether / how often till now
Example:
Have you ever been to Canada? / I have been to Canada twice.

Emphasis on action or result?

Do you just want to express what happened in the past? Or do you want to emphasise the result (a past action's consequence in the present)?
Simple Past Present Perfect Simple
Emphasis on action
Example:
I bought a new bike. (just telling what I did in the past.)
Emphasis on result
Example:
I have bought a new bike. (With this sentence I actually want to express that I have a new bike now.)

Signal Words

Simple Past Present Perfect Simple
  • yesterday
  • ... ago
  • in 1990
  • the other day
  • last ...
  • just
  • already
  • up to now
  • until now / till now
  • ever
  • (not) yet
  • so far
  • lately / recently

Exercises on Simple Past and Present Perfect Simple

Tests on Simple Past and Present Perfect Simple



Present Perfect with Already, Just, Still & Yet Exercise

 

Just, yet, still, already

 
 http://www.eslcafe.com/grammar/present_perfect_tense06.html

Just, yet, still, already

These words are often used with the present perfect tense although yet, still and already can all be used with other tenses.

Just

Just’ is usually used only with the present perfect tense and it means ‘a short time ago’.
  • I’ve just seen Susan coming out of the cinema.
  • Mike’s just called. Can you ring him back please?
  • Have you just taken my pen? Where has it gone?
In the present perfect, ‘just’ comes between the auxiliary verb (‘have’) and the past participle.

Yet

Yet’ is used to talk about something which is expected to happen. It means ‘at any time up to now’. It is used in questions and negatives.
  • Have you finished your homework yet? The speaker expects that the homework will be finished.
  • I haven’t finished it yet. I’ll do it after dinner.
Yet’ usually comes at the end of the sentence.

Still

Still’ is used to talk about something that hasn’t finished – especially when we expected it to finish earlier.
  • I’ve been waiting for over an hour and the bus still hasn’t come.
  • You promised to give me that report yesterday and you still haven’t finished it.
Still’ usually comes in ‘mid-position’

Still is often used with other tenses as well as the present perfect.
  • I’ve still got all those letters you sent me.
  • Are you still working in the bookshop?
Already

Already’ is used to say that something has happened early – or earlier than it might have happened.
  • I’ve already spent my salary and it’s two weeks before pay day.
  • The train’s already left! What are we going to do?
Already’ usually comes in mid-position.

 Exercises:

 http://www.autoenglish.org/gr.presper.i.htm

 http://www.englishexercises.org/makeagame/viewgame.asp?id=3211

 http://perso.wanadoo.es/autoenglish/gr.presper.i.htm

 http://eslzone1.tripod.com/grammarinter/_yet.htm

 http://english123.milaulas.com/mod/resource/view.php?id=6&lang=en

 

 

 





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