Page 430 - Practical English Usage 3ed - Michael Swan, Oxford

3 past perfect not used
past perfect (2): advanced points 424
The past perfect is nonnally only used as described above. The past perfect is not used simply to say that something happened some time ago, or to give a past reason for a present situation.
Alex Cary, who worked for my father in the 1980s, is now living in Greece. (NOT l~J~ Cary, wh6 lttttl ftl6rketi JVJr my fathe#' ...)
I left some photos to be developed. Are they ready yet? (NOT llttttlleft S6me ph6ffls •..)
4 unreal events: if etc
After if (see 259), wish (see 630) and would rather (see 491), the past perfect can be used to talk about past events that did not happen.
IfI had gone to university I would have studied medicine. I wish you had told me the truth.
I'd rather she had asked me before borrowing the car.
S how long? past perfect, not simple past.
We use a past perfect, not a simple past, to say how long something had continued up to a past moment. A simple past perfect is used with 'non- progressive verbs' like be, have and know.
She told me that her father had been ill since Christmas. (NOT • • . that he, folther WftS ill sif'lt'e ChrisfflittS.)
I was sorry to sell my car. I had had it since College. (NOT ..... had it ainee CtJUege.)
When they got married, they had known each other for 15 years. (NOT ••• they knew etteh other JVJr 15 yea,s.)
With most other verbs, we use the past perfect progressive for this meaning (see 425).
For the difference between since and for. see 208.
424 past perfect (2): advanced points
1 past perfect or simple past with after, as soon as, etc
We can use time conjunctions (e.g. after, as soon as, when, once) to talk about two actions or events that happened one after the other. Usually the past perfect is not necessary in these cases, because we are not 'going back' from the time that we are mainly talking about, but simply moving forward from one event to the next.
After it got dark, we came back inside.
As soon as Jane arrived, we sat down to eat.
Once it stopped raining, we started the game again.
However, we can use the past perfect with after, as soon as etc to emphaSise that the first action is separate, independent of the second, completed before the second started.
She didn't feel the same after her dog had died.
As soon as he had finished his exams, he went to Paris for a month.
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