31. If you brush your teeth everyday, you won't have a toothache.
32. she asked me if I would be free the next day.
33. She asked me if you spoke any other language.
34. The computer which was broken yesterday has been repaired. 
35. She asked me if I could speak English.
36. Peter asked what I was going to early.
37. In spite of his broken leg, he went to school.
38. I used to go swimming after school every afternoon when I was a school boy.
39 Lan got up late,so she missed the bus this morning.
40. She is interested in listening to pop music.

30 She asked me if I was going that day

31 If you brush your teeth everyday,you won't have a toothache

32 She asked me if I would be free the following day

33 She asked me if I spoke some other languages

34 The computer which was broken yesterday,has been repaired

35 She asked me if I could speak English 

36 Peter asked me what i was going to study 

37 In spite of his broken leg,he went to school

38 I used to go to swimming after school every afternoon

39 Lan got up late ,so she missed the bus this morning 

40 She is interested in listening the pop music

41 How long have you met him?

42 This is the first time he has been to Canada

43 Maty is interested in watching cartoon film

44 It takes him most of his free time to play video game

45 I spend 3 hours doing this work

46  Unless you take notice,you can't solve this problem ourseves

47 If you take a map,you won't get lost

48 If you learn hard , you won't fail the exam

49 If many people didn't cut down trees,the weather wouldn't change a lot