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1. The boy is helped by Mai.
2. Lan's homework is done.
3. Flowers in the garden are cut by her every morning.
4. The exercises are done well.
5. The garages are cleaned every morning.
6. The bread is wrapped automatically by the machine.
7. Every car engine is checked thoroughly.
8. This computer is exported to seventy different countries.
9. These books were bought from that store by Mary.
10. That house was destroyed by fire.
11. The concert was enjoyed very much by the audience.
12. The accident was seen by Mr.Smith.
13. The report was left on the desk.
14. This film will be seen soon.

15. It can be seen by you now.

1. The boy is helped by Mai.

2. Lan's housework is done by her.

3. Flowers in the garden are cut by her every morning.

4. The exercises are done well by them.

5. The garages are cleaned by us every morning.

6. The bread is wrapped automatically by the machine. 

7. Every car engine is checked thoroughly by us.

8. This computer is exported to seventy different countries by us.

9. These books were bought from that store by Mary.

10. That house was destroyed by fire.

11. The concert was enjoy very much by the audience.

12. The accident was seen by Mr. Smith.

13. The report was left on the desk by him.

14. This film will be seen soon by everybody.

15. It can be seen by you now.