The Past Perfect
1. Comparing past events
We use the past perfect when we want to emphasize that one past event happened before another past event.
The action which happened first uses the past perfect.
When I arrived at the station, the train had left. (the train left before I arrived)
2. With when
If we want to emphasize that one action happened before another, we can use when + past simple.
When she arrived at the party, everyone had left. = everyone left before she arrived
(past simple) (past perfect)
3. With time expressions
We can use the past perfect with time expressions to express that the action in the past perfect happened before the action in the past simple.
We can use: when, before, after, as soon as, by the time, the moment, immediately, till, until, etc.
When I had finished the project, I called my boss.
As soon as they had arrived at the hotel, they went to bed.
She didn’t know how funny he was, until she had met him.
4. With adverbs
We can use the past perfect with the following adverbs: just, already, never and ever.
Peter had already begun cooked dinner, when his wife arrived.
She had just completed her first book, when the editor contacted her.
5. As the equivalent of the present perfect
We can use the past perfect as an equivalent of the present perfect when we are looking back from the past.
It was 2003 and she had just arrived in New York.
He had worked for T&T Co. for 5 years when he was promoted.
6. With reported speech
We use the past perfect in reported speech when the original sentence was in the past simple or in the present perfect.
From past simple to past perfect:
‘I went to the cinema three times last week.’, he said
He said that he had gone to the cinema three times the week before.
From present perfect to past perfect:
‘Have you ever been to New Zealand?’, she asked.
She asked if I had ever been to New Zealand.
7. With if, wish and if only
We use the past perfect in subordinate clauses to express an unreal past situation.
I wish you had told me about the problem.
If you had told me about the problem, I could have helped you.
If only she had sent me an email.
I would rather we had gone home on time.
8. Past simple or past perfect?
In most cases, we can use either the past simple or the past perfect. The past perfect is used to show which action happened first when it is important.
After I finished work, I went home. = After I had finished work, I went home.
However, we must always use the past perfect when we talk about unreal past situations
