3.I haven't seen Peter for five years.

5.She likes watching romantic comedy film.

6.This is the first time I have eaten such a delicous cake.

7.Paris is the most beautiful city in the world.

8.This is the first time I have seen this boy.

9.If we use the car all the time, the air will dirty.

10.Unless I leave now, I will miss my train.

11. If I don't have to do everything myself , I won;t have a modern robot.

12.Minh is very intersted in  teaching robot.

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1. I have never met him before.
2.No one in my class is more intelligent than her.
3. I haven't seen Peter for five months.
4. Living in Hanoi is more expensive than living in Hoa Binh.
5. She likes watching romantic comedy films.
6. This is the first time I have eaten such a delicious cake.
7. Paris is the most beautiful city in the world.
8. This is the first time I have seen this boy.
9. If we use the car all the time, we will make the air dirty.
10. Unless I leave now, I'll miss the train.
11. If I don't have a modern robot, I won't be able to do everything myself.
12. Minh is very interested in teaching robots very much.