#1
1 understood-had got
2 didn’t have-had bought
3 arrived -had already closed
4 didn’t play-had hurt
#2
2 had forgotten
3 had happened
4 had he gone
5 had met
6 hadn’t been
#3
1 When I had done my homework,I sat down to watch TV.
2 When Leo had had a bath,he went to bed.
4 When they had made a report ,they went to bed.
5 When Clara had read the book,I borrowed it.
6 When we had arranged a new meeting,we went home.