A．confusing B．mixing

C．confused D．mixed

答案与解析：C　confuse后面加－ed或－ing可以构成形容词，－ed形式具有被动意义；－ing形式具有主动意义，该题中表示被动含义。

5．________ with the old days, we are living a happier life now.

A．Compared B．Comparing

C．Compare D．In comparison

答案与解析：D　选项A、B都是分词形式，要求逻辑主语和句子的主语一致，所以只能用介词短语。

6．-Would you please give him the paper the moment he________？

-No problem.

A．arrives B．appearing

C．came D．reaches

答案与解析：A　考时间状语从句中时态的用法。the moment可用来引导一个时间状语从句，相当于as soon as引导的从句，用一般现在时表示将来。

7．The students ________ in character are quite similar in their interests.

A．differ B．different

C．difference D．who is different

答案与解析：B　主语the students后面跟的是定语，所以用different，相当于定语从句who are different。

8．You can't imagine the difficulty he ________ onto the cliff and saving the boy in trouble.

A．had to climb B．had climbed

C．had climbing D．had on climbing

答案与解析：C　difficulty后面是定语从句，这是句式had difficulty(in) climbing...被分解开了。

9．Most students don't follow the teacher's advice that they ________ some good sentences every day.

A．recite B．recited

C．be reciting D．be recited

答案与解析：A　句中的that从句为同位语从句修饰"advice"，表示建议应该做某事用虚拟语气，答案为A项，省略should。

10．The effect of the medicine ________ in a short time and he again felt painful.

A．wore out B．wore off

C．wore away D．wore down

答案与解析：B　根据题干的意思，此处指药效逐渐消失，所以答案为B项。

11．She probably didn't attend the meeting, ________ I didn't see him during the meeting.

A．because B．for

C．since D．now that

答案与解析：B　根据题干，后面说明的原因不是必然原因，只是个补充说明，所以应用for，其余选项不符合题意。

12．If you do ________ him, he will ________ of you in the class election.

A．a favor to; be in favor

B．a favor；in favor

C．a favor for; be in favor