题目内容
Now scientists are _________ to solve the problem about river pollution.
[ ]
A.making an attempt
B.made attempt
C.made a lot of attempt
D.attempted
答案:A
解析:
解析:
|
从句子结构和语态分析来看 B、C、D三项均与are构成被动语态,但与句意不符。 |
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