Ответ:
1) I read the book which I ( bought/had bought/ was buying)in Kyiv.
2) The boys were playing tennis while the girls (read/ was reading/were reading)
the magazines.
3) I came home after I (had finished/ finished/ was finishing) my work.
4) Peter opened the book and (started/ had started/ was started) reading it.
5) They presented me a vasel (had always dreamt/ dreamt/ was dreaming) about.
6) Before doing this task pupils (learnt/had learnt/ were learning) the new words.
Объяснение: