题目

我要问几道英语选择题,请给以具体解答,1、The air inside a house or office building often has
higher concentrations of contaminants_______ heavily polluted outside air.
A.than does B.more C.as some that are D.like of
2.________ did we ask him not to smoke while on duty.
A.Ever B.Never C.Often D.So
3.World trade in services has grown twice as fast as _____ over the past decade.
A.merchandise trade did B.has merchandise trade C.grew merchandise trade D.merchandise trade had

提问时间：2020-11-03

答案

1、选A
首先,句子缺少谓语,排除B、D.
然后,根据句子得知前后是个比较的关系.故应该是对air的对比,故为单数.选A.
2、选C
这个是一个倒装,Never 用于否定句,与did不符；so倒装,表示“也”；Ever翻译不通顺.
3、选A
相当于第二个as后跟了一个从句,应该为正常语序.as.as是一个比较的句子,后面的谓语动词应该换为对应的助动词或be动词形式.