Past Perfect

Take a look at this example:

Paulina had written the letter before the class started.
Now she gave it to Mark.





The past perfect is used to refer to an event or situation which took place before another past event.

 

To help you to make it clearer:

more examples:

- I had lived in Spain for three years before I got married.

- She knew she hadn't studied it before the teacher called her to the blackboard.

And now compare the examples above with these similar examples in the present perfect. 

The only difference is that these examples are talking about the present:

- I have lived in Spain for three years. (until now)

- She knows that she hasn't studied at all, and now the teacher is calling her at the blackboard.

In these last examples we refer at the time of speaking, in the previous examples we refereed something before another event, therefor we used the past perfect.

Present perfect and Past simple

Most of the students, find difficult the circumstances of when it should be used either present perfect or past simple.
example:

Mark is looking for his wallet. He can't find it.
Mark has lost his wallet. (action, present perfect)

That means that he is not in possess of his wallet, at the time of speaking, now.


and a few minutes after..


Now Mark has found his wallet. He has it now.
Has he lost his wallet? No, he has found it.
Did he lose his wallet? Yes, he did.

He lost his wallet,            (before, present simple)
but now he has found it!  (now, present perfect)



The present perfect is a present tense. It always tells us about the situation now. The present simple tells us only about the the past, it doesn't tell anyting about the situation now.

This scheme represents most of the past tens, we have seen so far:

Note:

• Present perfect is used for new or recent happenings: I've just seen a nice advertisement on TV
• Past simple is used for things that are not recent or new: My grandfather grew up in Sardinia, then he moved to Italy when he was 35 years old.

Compare the examples:
- Who invented the first car?
- Do you know if the Europeans car manufacturers have invented some new eco-engine?

• Present perfect is used to give new information, but if we continue to talk about it, we normally use the past simple.

more examples:
- I've just cut my finger!
- Are you ok? I'll bring you a plaster.
- Yes please, take here the whole first Aid box.
- How did it happened?
- I cut myself with the new knife, is so sharped!

Do not forget, what we said in the previous lessons:

• Present perfect is not used when is refered to a finished time (yesterday, in 1980, yesterday, when i was a child): last weekend was soo cold.
• When in the sentence there is When or What time, it must be used the Past simple: what time did you get home last night?

more examples:
- It hasn't snowed yet this year.     (Present perfect)
- It didn't snow last year.               (Past simple)

- at breakfast time: Have you shaved this morning?         (Present perfect)
- at dinner: You didn't shave this morning, isn't?               (Past simple)

- I have never been in Tunisia.    (Present perfect)
- I was in Tunisia in 2005.           (Past simple)

Past simple

Example:

George Washington led the American victory over Great Britain in the American Revolutionary War as commander-in-chief of the Continental Army in 1775–1783, and presided over the writing of the Constitution in 1787. In 1789 he became the first President of the United States. He died in December 1799.





Led, presided, became, died are all verbs in past simple tense.
Very often the verbs in past simple tense end in -ed
- I worked so hard yesterday.
- I studied very hard, to pass this exam.
- I called you two days ago.

Many verbs are irregular: the past simple in the irregular form does not end in -ed
examples:
go     -   went 
be     -   was
see    -   saw
think -   thought
tell    -   told

[ We will speak about irregular verbs in further Unit ]

In questions and and negatives we use did / didn't + infinitive
examples:
You saw           Did you see?           She didn't see
I said                Did you say?           I didn't say
They spent       Did they spend?       They didn't spend

You invited me for the party last week, but i didn't come.
Did you go to party last weekend? No I didn't go out.
Penny lost her mobile, so she didn't call me

In the following examples, do is the main verb in the sentence:
I didn't do my homework
Did she do the list?

The past of the verb to be is
I was                         I wasn't                       Was I?
You were                  You weren't                  Were you?
He/She/It was           He/She/It wasn't          Was He/She/It?
They were                 They weren't                Were they?

Note that we do not use did in negatives and questions with was/were
examples
Did you go out for dinner last night or you had food at home?
Yesterday she wasn't able to finish her work because she was so busy.