Chuyển sang thể bị động

1.Tam learns english everyday
2. Mr.Pike bought a new car yesterday.
3. Tam is reading a book now. 
4. They can’t make tea with cold water. 
5. The chief engineer was instructing all the workers of the plant.
6. Somebody has taken some of my book away. 
7. They will hold the meeting before the may day
8. They have to repair the engine of the car 
9. The fire has destroyed many houses. 
10. People spend a lot of money on advertising everyday. 
11. They may use this room for the classroom. 
12. The teacher is going to tell the story.
13. Mary is cutting the cake with a sharp knife.
14. They have provided the victims with food and clothing.
15. They told the new students where to sit.
16. John used to visit Mr.Cole at weekends.
17. People speak English all over the world.
18. They will build a new school next year. 
19. My mother had written the letter before 1985. 
20. I’m cleaning my room.