Chuyển sang câu bị động:

**Present Perfect Tense:**

1. The play has already been watched by me before.
2. Our city has been destroyed by the 1999 flood.
3. His pencil has been used by him instead.
4. This is the first time such a lovely dog has been seen by me.
5. The homework hasn't been done by the student yet.
6. She has been taken to the hospital by them.
7. The meeting has been cancelled by them.
8. My chair has been moved by someone.
9. He has been given a lot of money by someone.
10. All the students in the school have been invited by us.
11. He has been told not to be late again by us.
12. The English grammar has been explained by our teachers.
13. Have the above sentences been finished by you?
14. The mugger has been arrested by the police.
15. Five suspects have been arrested by the police.

**Past Perfect Tense:**

1. Their homework had been finished by them before they went to the cafeteria.
2. The housework had been done by her husband before the party yesterday.
3. Before going shopping yesterday, the kitchen had been cleaned by David.
4. The video game had been played by Wonbin for four hours.
5. The film hadn't been seen by Ms. Nina before.