1. Rang - was watching
2. Were you driving - happened
3. Were making - arrived
4. Went - were having - came
5. Began - was sitting
6. Were you doing - was working
7. Was - left - was falling
8. Saw - were trying
9. Was walking - felt - didn’t know
10. Were driving - appeared
11. Were you doing
12. Was reading
13. Saw - didn’t see - was looking
14. Met - were going - was going - had - were waiting
15. Was cycling - stepped
16. Went - managed - didn’t hit
17. Did you go
18. Took = wasn’t looking
19. Saw - was trying
20. Was walking - heard - was following - started 

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Cách sử dụng thì QKTD: 

1. Diễn đạt hành động đang xảy ra tại một thời điểm trong quá khứ tiếp diễn. Trong câu xuất hiện trạng từ while + mệnh đề chia thì quá khứ tiếp diễn, ta chia mệnh đề còn lại theo thì quá khứ tiếp diễn để diễn tả 2 hành động xảy ra cùng 1 lúc trong quá khứ

2. Diễn đạt hai hành động xảy ra đồng thời trong quá khứ

3. Diễn đạt hành động đang xảy ra thì có hành động khác xen vào

4. Hành động lặp đi lặp lại trong quá khứ và làm phiền đến người khác