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

xin hn cho nhóm

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

+do vế sau là chia ở quá khứ tiếp diễn nên vế đầu cx chia ở qk tiép diễn

2 , What were you going / 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