31. That old house has just been sold.

`->` Câu bị động hiện tại hoàn thành: S + have/has + been + Vpp

32. Although the weather was bad, they had a wonderful holiday.

`->` Although + S + V: mặc dù

33. A new mall will be built here.

`->` Câu bị động tương lai gần: S + will be + Vpp

34. If he doesn't take these pills, he won't be better.

`->` If 1: If + S1 + Vs/es, S2 + will + Vinf

35. It is the first time I have ever been here.

`->` It is the first time + hiện tại hoàn thành

VI

36. If it doesn' rain tomorrow, I will go camping with my friends.

37. It is necessary for you to practice English every day.

38. I have never travelled by air.

39. The students are studying for their exam now.

40. It is such a cold day that we decide not to go out.

V.

`31`. That old house has just been sold.

`32`. Although the weather was bad, they had a wonderful holiday.

`33`. A new mall will be built here.

`34`. If he don't take these pills, he won't be better.

`35`. It is the first time I have been here.

VI.

`36`. If it doesn't rain tomorrow, I will go camping my friends.

`37`. It is necessary for you to practice English every day.

`38`. I have never travelled by air.

`39`. The students are studying for exam now.

`40`. It is such a cold day that we decide not to go out.