31. When we __were__ at school we all __studied__ Latin. ⇒ Cấu trúc: When + QKĐ, QKĐ
32. When I __met__ him, he __had been working__as a waiter for a year. ⇒ Cấu trúc: When + QKĐ, QKHT.
33. After he __had finished__ breakfast he __sat__down to write some letters.
34. She ___has___a hard life, but she's always smiling. ⇒ không có thời gian nhất định, dùng HTHT
35. I think Jim __has been__ out of town. ⇒ không có thời gian nhất định, dùng HTHT