He said he had seen that movie. (He said: "I have seen that movie.") By the end of last week he had finished the first part. (The past time phrase requires a past tense.) They were selling the house they had built. (The house was built earlier in the past.)
1.3 To start a past conditional phrase Use this tense to state the past condition in a conditional phrase.
If you had studied better, you would have passed the exam. (You did not study when you should have and failed the exam.) If you had listened to me earlier, everything would have gone differently. (You did not listen to me when you had the chance.) Had I realized that it was you, I would have said hello. (I didn’t realize it was you and said nothing.)
Zamon ko’rsatkichlari: For
By+last time
Before + S + Vpast, + S + had + VPII After + S + had + PII + S + Vpast
No sooner ... than Barely ... when Scarcely ... when Hardly ... when