1. Everyone went to work as usual 

2. My father gave up smoking five years ago.

3. I'm looking for my diary.

4. They'll have put off the game.

5. My sister took care of our children when we went to Saigon.

6. Mr. Ba suggested going abroad for our holiday this year.

8. I suggest you should install enegy-saving appliances in your house.

9. Unless you study harder, you will fail the next exam

10. Mr. Phong didn't go to work yesterday because he didn't feel well.

11. It rained very hard. However, he went out without a raincoat.

12. If you keep your room clean, you will have an idea place to live.

13. Water pollution prevented us from swimming in that part of the River.