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37. You didn't forget to post the letter, did you?
38. It takes six hours to fly from London to New York.
39. Not only did he spend all his money but he borrowed some from me as well.
40. We always remember spending our childhood in that beautiful mountain resort.
41.The circus show which the whole family enjoy are exciting.
42. Le Van Tam was so brave that everyone admired him.
43. This is such a difficult problem that I can't explain it.
44. Almost all the houses in the neighborhood have been destroyed by the fire.
45. The bank manager was made to hand over the money by the robbers.
46. She told me that she didn't remember what she had done the day before.
47. If he had taken my advice, he wouldn't have got in trouble.
48. This is the first time I have eaten with knives and forks.
49. The road isn't large enough for two cars to pass each other.