Put the verbs in brackets into the past simple ,past continuous,past

Put the verbs in brackets into the past simple ,past continuous,past perfect or past perfect continuous . 19. Tom didn't come with us last night because he (arrange) to go out with colleagues after work. 20. Before they invented washing machines people (wash) their clothes by хэнд for centuries . 21. Peter (talk) on the phone when i went to his office ,so i didn't want to interrapt him . 22. What time you (go) to the pool yestarday . Помогите пожалуйста