四．单词拼写（10分）

51. Great changes have t______________ place in my hometown in the last ten years.

52. His parents died in an accident. He was b______________ up by his uncle.

53. He thinks that I like the coat very much, but on the c_________, I don’t like it at all.

54. We have b________________ a lot from his advice. His advice is of great use to us.

55. Smoking is not p__________________ in the office.

56. She eats a little in order to lose w_______________.

57. I am looking f________ to his letter. I haven’t got any news from him for a long time.

58. He did something wrong, so he a____________________ to his father for it.

59. He failed in his business, so he is in d____________.

60. Don’t believe him. He is always telling l_______________.

一平面简谐波在弹性介质中传播，在介质元从最大位移处回到平衡位置的过程中（）。

A.它的势能转换成动能

B.它的动能转换成势能

C.它从相邻的一段介质元中获得能量，其能量逐渐增大

D.它把自己的能量传给相邻的一介质元，其能量逐渐减小