6. We have finished/finished our homework already. Can we go outside now?
=> dấu hiệu : already
7. When he has been/was 10 years old, he went to school in New York.
=> quá khứ đơn
8. Suzy hasn't read/read the third book in the series yet.
=> dấu hiệu : yet
9. Have you ever met/Did you ever meet the new mentor before?
=> dấu hiệu : before
10. What have you done/did you do so far with that non-profit organization?
=> dấu hiệu : so far
11. Did they offer coupons for free pizza in Royal City last week? - Yes, they have./Yes, they did.
=> dấu hiệu : last week
Ex3.
12. Have you ever worked as a volunteer? Đúng
13. I have cleaned up my room last week.
=> cleaned
14. I have stayed in San Francisco for two years.
=> has
15. Did she never used public transport?
=> have
16. Last month, we started a community garden project. Đúng
17. Yesterday, I've gone to the nursing home to visit my grandfather.
=> went
18. She hasn't finished her work yet. Đúng
19. Hey Tom! Did you cook a meal at a shelter for homeless people last week? Đúng
20. They raised 20 million dong for the fund so far.
=> have raised
xin ctlhn