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2. Minh spends 2 hours doing his homework every day.
3. They haven't visited me for 3 months.
4. My friend asked me what I was studying then.
5. Although Mr.Jackson is old, he runs 10 kilometers a day.
A/
1. Their city was destroyed by the storm last year.
2. She asked Mary what subject she liked best.
3. I used to live in London when I was a child.
4. The skirt is not as cheap as the dress./The skirt is more expensive than the dress.
5. Although the joke was funny, no one laughed.
6. She is not old enough to decide herself.
7. If the weather were nice today, we would go for a picnic.
8. Nam, who is a friend of mine, lent me that book.
9. It's 2 months since he last wrote to his parents.
10. The boy wishes he had his teacher's address.

I/
1. This shop was bought last year.
2. Chi enjoys listening to music.
3. Minh spends 2 hours doing his homework every day.
4. Because it rained heavily, we were late for school.
5. She said that she was a teacher.