đáp án là
1. Whe haven't seen her since Christmas.
2. This is my first time I have eaten this kind of food.

3. It has rained for an hour.

4. The last time we visited my grandfather was in mốc thời gian / khoảng thời gian ago

5. I began studying english  three years ago.

6. It's nearly five years since my brother has seen his beat friend.

7. How long have you learnt English?

8. We have lived here for fifteen years

9. She hasn't visited me for five years.

10. I haven't written to my uncle since July.

11. We have become close friend for a long time.

12. Minh has collected stamps since 2000.
chúc học tốt