15、―― We did not see him at the lecture yesterday. 

―― You _____ him, since I went to an international conference with him.

A. mustn’t have seen                                  B. can’t have seen

C. couldn’t see                                          D. needn’t have seen

14、Strawberries can, of course, be frozen but they taste best when bought and eaten _____.

A. fresh                 B. freshly                     C. more freshly              D. fresher

13、It is one thing to enjoy listening to good music, but it is quite _____ to perform skillfully yourself.

A. any other           B. another              C. other thing         D. some other             

12、 If you read _____ the lines, you will know that they don’t really welcome us to attend the meeting.                                                              

A. within               B. in                      C. between            D. at

11、在过去的三十年里，中国人民以巨大的勇气、信心和创造力取得了了不起的成就，这令整个世界震惊（…, which … ）

二、选择题

（每空？ 分，共？ 分）

10、人们普遍认为学会合作有利于问题的解决。 (It … )  

9、夏天还没到呢，孩子们就迫不及待地想游泳了。 （wait）

8、一旦你承诺要做某事， 就要守信用。 （once）

7、一个人年轻时多学点是有好处的。 (beneficial)

6、考试时一定要仔细。 （in）