Viết lại câu với dạng bị động

2. You must clean the wall before you paint it.

3. They told the new pupil where to sit.

4. I knew that they had told him of the meeting.

5. Nobody has ever treated me with such kindness.

6. No one believes this story

7. A sudden increase in water pressure may break the dam

8. We must take good care of books borrowed from library

9. A man I know told me about it

10. We can never find him at home hor he is always on the move

Các bạn giúp mình nha. Cảm ơn nhiều