4/

1. John  used to smoke a lot a year ago.

2. It's time you went to school.

3. When did you last see Tom?

4. I'd rather you keep silent in the classroom.

5. He wishes he could pass the examination.

6. We wish we could go out.

7. I'd rather you not come to class late.

8. I wish we could come here.

9. They used to not go to Vung Tung at the weekends.

10. I wish I could help you.

11. We started learning English 4 years ago.

12. My father has given up smoking since last year.

13. They started working in that factory in 2001.

14. I last saw her a long time ago.

15. How long ago did you start learing French?

5/

1. I am writing this letter to complain about some people who caught fish in the public lakes.

2. What makes me worried is that they used dynamite to catch fish.

3. This kills not only fish but also other water creatures.

4. I would suggest that you fine them heavily.

5. Iam looking forward to seeing your solution.

Study well!