Помогите раскрыть скобки, поставить глагол в нужный залог и время,пожалуйста
1)My sister(to invite) to the birthday party by her friend yesterday.
2)More and more houses(to build) in our country from year to year.
3)We(to open) the window after every lesson.
4)We(to finish)our experiment in a week.
5)Young trees(to plant)in the street last autumn.
6)I(to answer)my brothers letter last week.