I. Chuyển các câu sau sang câu bị động

1. Mary types letters in the office.

2. His father will help you tomorrow.

3. Science and technology have completely changed human life.

4. Peter broke this bottle.

5. They are learning English in the room.

6. Nothing can change my mind.

7. No one had told me about it.

8. I don't know her telephone number

9. My students will bring the children home.

10. They sent me a present last week.

11. She gave us more information.

12. The chief engineer was instructing all the workers of the plan.

13. They can't make tea with cold water.

14. Somebody has taken some of my books away.

15. They will hold the meeting before May Day.

16. They have to repair the engine of the car.

17. The boys broke the window and took away some pictures.

18. People spend a lot of money on advertising every day.

19. Teacher is going to tell a story.

20. Mary is cutting a cake with a sharp knife.

21. The children looked at the woman with a red hat.

22. They have provided the victims with food and clothing.

23. People speak English in almost every corner of the world.

24. You mustn't use this machine after 5:30 p.m.

25. After class, one of the students always erases the chalk board.