Нужно сделать из активного залога в пассивный.
1. By the middle of autumn the students had planted all the trees.
2. They were destroying an old bridge over the river all day yesterday.
3. They will show this opera on TV next Sunday.
4. Nick broke the window in the classroom last week.
5. I usually plant potatoes at the end of May.
6. They will have built excellent shelters for tourists in these mountains.
7. The instructor has explained the rules of the game to the players.
8. They are building a new concert hall in our street.