74. Do you know how much colors there are in a rainbow?
A B C D ( )__________
73. Mary felt happily because her aunt gave her a present.
72. He would not mind do extra work for his school.
71. I don’t know what to wear. Could you give me some advices?
70. The life in a middle school isn’t ________ (real)boring.
C) 下列各句A、B、C、D中有一处错误，请在不改变句子意思的前提下，将正确答案写在题后的横线上。
69. The boy tried to open the juice can with a opener but ________ (fail).
68. Do you know if there is any ________ (different)between “see” and “look at”?
67. The girl practices _______ (play)the piano for two hours every day.
66. Jim is happy to live on the ________ (twelve)floor because he enjoys the scene out of the windows.
65. They are so kind to help us ________ (解决)many problems when we are in trouble.
B) 根据句子意思，用括号中所给单词的适当形式填空。