=>
1. played/was (when I was a child -> QKĐ)
2. was waiting/met (QKTD when QKĐ)
3. smoked/worked (các sự việc trong QK -> QKĐ)
4. to ask (used to V : đã từng làm gì)
5. was learning/heard (while QKTD)
6. wasn't writing/came/was writing
7. didn't play/were
8. to living (be used to Ving : quen làm gì)
9. to getting (get used to Ving = be used to Ving)

1. I played games when i used to be a child (Past simple)

2. She was waiting for the bus when she met an accident. (Past continous)

3. We always smoked when we worked in Ha Noi (Past simple)

4. My teacher used to ask us to do a lot of homework. (Past simple)

5. While she was learning, she heard a scream. (Past continous)

6.Hung was not writing an essay when i came, he was writing a letter. (Past continous)

7. They was not play chess when they used to be young. (Past simple)

8. She is used to live alone. (Past simple)

9. She isn't getting used to get up early. (Past simple)