21. wouldn't do 

if 2: If + QKD, S + would / could + v1 

22. turning 

suggest + Ving: đề nghị 

23. making 

How about  +Ving?đưa ra ý kiến, đề nghị 

24. haven't seen 

DHNB: since last Christmas (HTHT)

S + has/have + V3/ed 

25. Because the weather is highly polluted, we can not swim in this part of the river.

Because + clause, clause: bởi vì 

26. The "Green Aunday" was short. However, the students enjoyed it very much.

Clause +however + clause: tuy nhiên 

27. Mary's eyes are weak. Therefore, she has to wear glasses.

Clause + therefore+ clause: vì vậy 

28. Although their cultures are different, they immediately become friends.

Although + clause, clause: mặc dù 

29. If Phong had enough money, he would buy a house.

if 2: If + QKD, S + would / could + v1 

30. My English teacher suggests that I should write sentences with new words.

S + suggest + (that) + S + (should) + V1: đề nghị 

31. If you don't stop talking, you won't understand the lesson.

If 1: If + HTĐ, S+  will/can/shall ..  +V1 

32. The street which leads to my village is rather small and bumpy.

N (vật)+ which + V / S +V 

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