Viết các tập hợp sau bằng cách chỉ ra tính chất đặc trưng của phần tử

a) A=(2,3,5,7,11)

b) B=(0,4,8,12,16,20)

1. He spent lots of time doing this experiment.

…………………………………………………………………………………………..

2. It took me all the morning to prepare for lunch.

…………………………………………………………………………………………..

3. Anna spent three days visiting VN.

…………………………………………………………………………………………..

4. It took my son three years to study in this college.

…………………………………………………………………………………………..

5. I spend two hours doing my homework everyday.

…………………………………………………………………………………………..

6. They spent ten days painting this house.

…………………………………………………………………………………………..

7. She spent 2 days tidying her room.

…………………………………………………………………………………………..

8. We used to go to school in half an hour.

…………………………………………………………………………………………..

…………………………………………………………………………………………..

9. My sister often spends 30 minutes reviewing our lesson before class.

…………………………………………………………………………………………..

10. It took him twelve hours to fly from Hanoi to London.

…………………………………………………………………………………………..

11. It takes Jill 10 minutes to put on her makeup.

…………………………………………………………………………………………..

12.  It took us three days to repair his car.

…………………………………………………………………………………………..

13. I will spend two weeks reading the new book.

…………………………………………………………………………………………..

14. A good chef spent an hour cooking this meal.

…………………………………………………………………………………………..

15. The flight to New York lasted six hours.

…………………………………………………………………………………………..

      Answer the following questions

16. How often do you go to the gym? (sometimes)

…………………………………………………………………………………………..

17. How often does the boy study in the library? (rarely)

…………………………………………………………………………………………..

18. How often did you get presents when you were a child? (frequently)

…………………………………………………………………………………………..

19. How often were you absent from your previous job? (never)

…………………………………………………………………………………………..

20. How often does she go to the dentist? (every month)

…………………………………………………………………………………………..