Đáp án:
1. letters are typed by Mary in the office.
2. You will be helped by his father tomorrow.
3. Human life have been completed changed by science and technology.
4. This bottle is broken by Peter.
5. English is learnt in the room.
6. My mind can't be changed.
7. it had't been told to me.
8. Her telephone number isn't known.
9. The children home will be brought by my students.
10. The present was sent to me last week.
11. More information were given to us.
12. All the workers of the plan were being instructing by the chief engineer.
13. Tea can't be made with cold weather.
14. Some of my books have been taken away.
15. The meeting will be hold before May Day.
16. The engine of the car is repaired.
17. The window was broken and some pictures taken away by the boy.
18. A lot of money is spent on advertising every day.
19. A story is going to told by teacher.
20. A cake is being cut with a sharp knife by Mary.
Vote cho mình hay nhất được không #^^