31.That old house have just been sell.      32.Although the weather was bad,they had a wonderful holiday.                              33. A new mall will be built here.                34. If he doesn't takes there pill,he won't be better.                                                        35. Although he works hard,he can't support his lage family.                               36. If it doesn't rain tomorrow,I will go camping ....                                                    37. If I met Ailen from outer space,I would invite their home and talk.               38. I have never travelled by air.                 39. The students are strardying for the exam now.                                                      40. It was such a cold day that we decided not to go out

31 - The old house has been sold 

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

33 - A new nail will be built here

34 - If he takes these pills, he will be better

35 - Although he works hard, he can't support his large family

36 - If it doesn't rain tomorrow I will go camping my friends

37 - If I met ailen from outer space I would invite their home and talk

38 - I have never travelled by air

39 -  The students are studying for the exam now

40 - It was such a cold day that we decided not go out