2.4.3 Past perfect
Rule: The past perfect expresses states or events that occurred previous to other states or events in the past, but is usually replaced by the simple past when the sequence of events (or states) is clear.
Examples of errors:
(1) I got in touch with old friends who live in other towns and who I did not see for a long time.
(2) I couldn't admit that I didn't ask them.
(3) I was very glad that my mother has baked apple cake.
(4) The reason was that he has eaten warm cake.
(5) I was glad I haven't eaten it.
(6) He is the only one who can tell you what had happened at school.
(7) During the sp6ech, I think Daniel will tell you what had happened.
(8) If it is true that Daniel had once stolen, it doesn't mean necessarily that he has a bad character.
(9) I know a boy who had been expelled for the same reason that Daniel was thrown out for.
(10) Theft I closed the door and wanted to et on the front seat of the car, but immediately after I had slammed the door Inky started to bark.
(l)-(5) illustrate contexts where the past perfect is appropriate, though not necessary in all cases.
One could say, for example,
I was glad I didn't eat it.
without any possibility of misunderstanding, but the simple past in (1) might be understood to mean either 'It took me a long time to get in touch with them', or 'I didn't see them (after getting in touch with them) for a long time'. In (6)-(9) there is no use of the simple past which would justify the past perfect. The time reference of slam in (10), logically, is previous to start, but since the meaning of after makes the sequence of events perfectly clear, the past perfect here sounds heavy and redundant.
Germans tend to overuse the past perfect in English, .because German has a much stricter interpretation of the sequencing of events in past time. For example, German can use the past perfect in the following sentence because, strictly speaking, hatte gedacht is previous to the moment--also in the past--when the speaker learned that his interlocutor was American:
Ach so, Sie sind also Amerikaner! Ich dachte/hatte gedacht, Sie waren Engländer!
In English, though, the simple past is used:
Oh, so you're American! I thought you were English!