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1. saw
2. used to be
3. used to be
4. fought
5. take
6. used to go
7. talked
8. built
9. used to have
10. used to be

Ex4/
1. How far is it from the park to the hospital?
2. It is three kilometers from here.
3. Is it far from the supermarket to the library?
4. Where is the National Museum?
5. The National Park is five kilometers from the University.
6. It is nearly 200 kilometers from Nghe An to Hanoi.
7. Is there any post office near here?
8. It is just a five minute walk from here to the parking lot.
9. It is 30 centimeters from the first row to the second row.
10. My house is near my school, so I walk.

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Ảnh 2/
Ex1/
1. They didn't use to play tennis twice a week.
Did they use to play tennis twice a week?
2. I didn't use to go to the gym three times a week.
Did you use to go to the gym three times a week?
3. Tennis didn't use to be a sport for rich people only.
Did Tennis use to be a sport for rich people only?
4. My father didn't use to take me to see soccer games on Saturday?
Did your father use to take me to see soccer games on Saturday?
5. He didn't use to buy a new tennis racket.
Did he use to buy a new tennis racket?

Ex2/
2. We used to play soccer in the past.
3. I used to get up earlier when I had work.
4. Tom used to do his homework in the evening.
5. Lan used to write to Mary twice a month. 
6. He used to work at night when he worked in the supermarket.
7. Did they use to watch TV in the past?
8. She used to play badminton in her free time.
9. They used to go swimming in the afternoon in 1990.

10. He used to be a doctor in that hospital.