$\text{II.}$

1.Mary burned/ burnt her hand when she was cooking  the dinner.

2.While we were crossing the street, the policeman shouted at us

( diễn tả một hành động khác xen vào một hành động xảy ra trong QK, " while " => QKTD.) 

3. While she was walking around the park, she saw Mr Smith 

4. I was very tired because I had been working all day yesterday 

( dấu hiệu : all day yesterday => chia verb ở QK.) 

QKHTTD diễn tả hành động mang tính liên tục xảy ra trước hành động khác trong QK ) 

5. What were you doing at this time yesterday? 

( dấu hiệu : at + giờ chính xác + TG trong QK.) 

6. Were you watching TV when I phoned you? 

7. We didn’t go out because it was raining 

8. The bell rang while I was taking a bath. 

9. Ann had been waiting for me when I arrived 

( hành động An đứng chờ xảy ra trước hành động "tôi" đến.) 

10. When I stoped at his house this morning, he was still sleeping. 

$\text{III.}$ 

1. He had already gone before I went there 

Dấu hiệu : already 

Thì QKHT diễn tả hành động xảy ra trước 1 hđ khác trong QK 

S + had + Vpp, before S + Ved