1. I haven't visited my grandparents when they returned to the countryside. Answer: 1. B (hadn't visited): ko có QKHTTD đi với QKĐ
2. He said that he was working for a foreign company in the city center powABсD Answer: 2. C (power) dùng sai tính từ
3. If Trang forgets her breakfast, she would be very hungry before lunchtime. Answer: 3. D (will be): cấu trúc cdk1: HTĐ+TLĐ 
4. We have gone to see a movie called "The Big Sea" last Sunday. Answer: 4. A (went) last Sunday là dấu hiệu nhận biết của thì QKD
5. A new bridge is going to be building in the area. Answer: 5. D (built) : câu bị động
6. I wish that my pen pal is here now. Answer: 6. B (were): cấu trúc: S + wish+ Vqkd : mong muốn ngược hiện tại
7. Mr. Binh is the man which is wearing a white shirt and a red ticABDC Answer: 7. C (tie): red tie : cái nơ đỏ
8. We are having a meeting about air pollution in our city in Friday morning. Answer: 8. D (on): dùng sai giới từ
9. Did Mr. Ba use to drive more careful than he does now? Answer: 9. C (carefully): trạng từ 
10. He'd go to England to study if he has enough money. Answer: 10. D (had): cấu trúc câu dk loại 2
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