Giải thích về các thì:

• Quá khứ đơn: Diễn tả một hành động đã xảy ra và kết thúc trong quá khứ. Dấu hiệu nhận biết: yesterday, last night, ago, in 2023,...
• Quá khứ tiếp diễn: Diễn tả một hành động đang diễn ra tại một thời điểm xác định trong quá khứ. Dấu hiệu nhận biết: at this time yesterday, when I was..., while I was...
• Hiện tại hoàn thành: Diễn tả một hành động xảy ra trong quá khứ, kéo dài đến hiện tại và có thể tiếp tục trong tương lai. Dấu hiệu nhận biết: since, for, ever, never,...

Bài làm:

1. If you went to bed earlier, you wouldn't be so tired.
2. We will go camping tomorrow if it doesn't rain.
3. She spends two hours working part-time at a supermarket near her house everyday.
4. When I came, they were talking happily about the last night's movie.
5. Have you seen Miss Jennifer since she left for France?
6. My mother hasn't cooked for me since I married my wife.
7. My grandfather has never flown in an airplane, and he has no intention of ever doing so.
8. He told me that he was going to take a trip to California the following week.
9. We have just decided to go to Nha Trang this summer.
10. In all the world, there are only 14 mountains that reach above 8,000 meters.
11. Right now I am attending class. Yesterday at this time I was attending class.
12. When I came, she was preparing for lunch.
13. Yesterday afternoon, we lost the ball while we were playing football.
14. My mum didn't drive home at six o'clock yesterday.
15. Where did they go at 1 pm yesterday afternoon?
16. I didn't read my book at ten o'clock last night.
17. Tom was watching the news when I arrived.
18. We broke the TV while we were moving into the new house.
19. Mai wasn't wearing her hat when I met her.
20. I didn't go to school yesterday because I was ill.
21. Did you see the sports programme last night?
22. My mum changed the channel while I was watching a good film.
23. Lan dropped her glass while she was having lunch.
24. It was raining when we arrived at the cinema.
25. I cried when the film finished.
26. They were watching the news while their parents went out.
27. The actors came on stage while the presenter was talking.