(Перетворіть речення на пасивні) 1. He is going to publish a new book.
2. They haven't started the game yet.
3. They could have broken the window.
4. We have to sign all the documents.
5. Nobody can lift that stone.
6. The student had cleaned the board before the teacher came in.
7. They didn't return the books.
8. They are serving dinner now.
9. The teacher punished the pupils.