Exercise 1: Change the following sentences into passive form.
1. This house was built last year.
2. He is helped every morning.
3. Their work has been stopped because of fog.
4. The letter was written the day before he left home last week.
5. Many trees was planed in this area.
6. These photos were taken when he went on a holiday last summer.
7. This building isn't visted very often.
8. He wasn't sent any money by us.
9. We were advised not to go out alone.
10. This area was destroyed by the floods.
11. My camera was stolen from my hotel room.