Unit 15. Past perfect(I had done)
A.I/we/they/you/it had(=I'd etc.)gone/finish etc.
The past perfect simple is had+past participle(gone/seen/finished etc.)
This is the starting poinit of the story. Then, if we want to talk about things that happened before this time,we use the past perfect(had...):
*When Sarah arried at the party, Paul had already gone home.
B.Had done(past perfect)is the past of have done(present perfect).Compare:
present perfect
* Who is that woman? I've never seen her before.
past perfect
*I didn't know who she was.I'd never seen her before.(=before that time)
C.Compare the past perfect(I had done) and past simple(I did):
* Was Tom at the party when you arried? No,he had already gone home.
but "Was Tom there when you arried?""Yes, but he went home soon afterwards."引自第44页
剑桥英语语法
