Collins Cobuild

Unit 61
The perfect tenses
Main points
You use the present perfect (‘I have walked’) to relate the past to
the present.
You use the past perfect (‘I had walked’) to talk about a situation
that occurred before a particular time in the past.
1
 You  use  the  present  perfect  tense  when  you  are  concerned  with  the
present effects of something which happened at an indefinite time in
the past.
I’m afraid I’ve forgotten my book.
Have you heard from Jill recently?
Sometimes,  the  present  effects  are  important  because  they  are  very
recent.
Karen has just passed her exams.
You  also  use  the  present  perfect  when  you  are  thinking  of  a  time
which started in the past and is still continuing.
Have you really lived here for ten years?
He has worked here since 1987.

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You also use the present perfect in time clauses, when you are talking
about something which will be done at some time in the future.
Tell me when you have finished.
I’ll write to you as soon as I have heard from Jenny.
2
When you want to emphasize the fact that a recent event continued to
happen for some time, you use the present perfect continuous.
She’s been crying.
I’ve been working hard all day.
3
You use the past perfect tense when you are looking back from a point
in  past  time,  and  you  are  concerned  with  the  effects  of  something
which happened at an earlier time in the past.
I apologized because I had forgotten my book again.
He felt much happier once he had found a new job.
Mr and Mrs Jones would have come if we had invited them.
You also use the past perfect when you are thinking of a time which
had started earlier in the past but was still continuing.
I was about twenty. I had been studying French for a couple of years.
He hated games and had always managed to avoid children’s parties.
4
 You  use  the  future  perfect  tense  when  you  are  looking  back  from  a
point  in  the  future  and  you  are  talking  about  something  which  will
have happened at a time between now and that future point.
In another two years, you will have left school.
Take these tablets, and in twenty-four hours the pain will have gone.
You also use the future perfect when you are looking back from the
present and guessing that an action will be finished.
I’m sure they will have arrived at the airport by now.

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It’s too late to ring Don. He will have left the house by now.
5
You can also use other modals with ‘have’, when you are looking back
from  a  point  in  time  at  something  which  you  think  may  have
happened at an earlier time.
I might have finished work by then.
He should have arrived in Paris by the time we phone.
For more information on modals with ‘have’, See Units
79
to
91
.

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