1. saw - hành động nhìn thấy cắt ngang việc chờ xe → dùng saw

2. were you doing - hành động gọi cắt ngang việc đang làm → dùng were you doing

3. didn’t visit - không có dấu hiệu thì QKTD → dùng didn’t visit

4. rained - không có dấu hiệu thì QKTD → dùng rained

5. was reading - 2 hành động cùng xảy ra song song → dùng was reading

6. ate - không có dấu hiệu thì QKTD → dùng ate

8. Did you find - không có dấu hiệu thì QKTD → dùng Did you find

9. did she dance - không có dấu hiệu thì QKTD → dùng did she dance

10. watched - không có dấu hiệu thì QKTD → dùng watched

$\textrm{Shipper Pro đây!}$

1. Alice saw/ was seeing the accident when she was catching the bus.

2. What were you doing/ did you do when I called?

3. I didn’t visit/ weren’t visiting my friends last summer holiday.

4. It rained/ was raining heavily last July.

5. While people were talking to each other, he read/ was reading his book.

6. My sister was eating/ ate hamburgers every weekend last month.

7. While we were running/ ran in the park, Mary fell over.

8. Did you find/ Were you finding your keys yesterday?

9. Who was she dancing/ did she dance with at the party last night?

10. They were watching/ watched football on TV at 7 p.m. yesterday