4. had made 

By the time + QKD, QKHT

QKHT: S + had+ V3/ed 

5. ends 

As soon as + HTĐ, TLĐ: ngay khi 

HTĐ: S  +V1/s/es

6. had seen

S + asked + O +if/whether + S + V (lùi thì)

ago--> before 

QKĐ --> QKHT 

7. would 

S + would + V1 : dùng ở quá khứ vì vế trước ở were working 

8. was 

S +  was/were + ADJ : thì QKĐ.

--> vì vế sau có couldn't + V1 

9. had drawn 

After + QKHT, QKĐ

10. to harvest 

in order to + V1: cụm từ chỉ mục đích 

11. had / would 

If 2: if + QKĐ, S + would / could + V1 

12. knew 

S + wish(es) + S+ V2-ed: ước ở hiện tại 

13. were / doing 

DHNB: at this time yesterday (QKTD)

S +was/were + Ving 

14. was reading / phoned 

QKTD + when + QKĐ

`color{orange}{~MiaMB~}`