一些中学英语易混结构分析(三)
16. Had I known her well , I would have invited her to the party .
当你看到would have invited 可以猜疑是虚拟语气结构，had I known her well 部分表示条件，属于虚拟语气条件从句省掉if 的情况，相当于if had I known her well ,省掉if 时，句子应倒装，省掉if 共有三种情况，当谓语动词是 (1)were ;（2）should do ;(3) had done 。应注意与一般疑问句Had I finished the work before he came back ?的区别。
17 . _________ was lying .
A. Whoever told you that B. No matter who told you that
Whoever 引导名词性从句或让步状语从句，no matter who 引导让步状语从句， 不能引导名词性从句，横线处是名词从句的位置，不是状语从句的位置，辨认状语从句应当看逗号，逗号后有句子主语。例如：No matter who told you that , he was lying .此句中的no matter who 可以用whoever 代替。Whoever told you that , he was lying .
18 ________ shall finish the work before May Day is possible.
A. We B. That we
此题往往在结构上搞错，认为意思上完整，不缺少含有意思的引导词，句意为：五一节前完成工作是可能的。选择了A。 其实，We shall finish the work before May Day is possible. 句子结构是错误的，May Day 之前是一个从句，应当有一个引导词, that 没有词义，仅起引导从句的作用。本题的答案应当是B。
19. Id rather you ______ something about it for the time being .
A. did B. to do
此句是结构问题，如果填did，把you did something 看成从句，如果填to do ，则把you 看成了宾格形式，前者正确，后者错误。Would rather 是一个助动词，不可能有宾语复合结构。此题只能选择A。would rather (that) + 从句 （从句中谓语动词用过去时）
意思为：宁愿某人做某事。
20.Is _________ that flows through that town ?
A. this river B. this the river
此题正确答案为B。如果选A，句子结构错误。此句是疑问句，把它变成陈述句结构就清楚了，This river is that flows through that town. (无句意)，试比较：This is the river that flows through that town. (这是一条流经那座城镇的河。)
21. As is known to all, the problem of pollution is serious.
It is known to all that the problem of pollution is serious .
前一句是定语从句，后一句是含有主语从句的主从复合句，往往学生搞错这两个结构，以问题形式出现，学生就会暴露出问题。
_________ known to everyone , the earth is round .
A. It is B. As C. As is D. As it is
正确答案是C。
22. I need a book , one which is cheap but useful.
I need a book , which is cheap but useful .
前一句是简单句， one 作 book 的同位语；后一句是含有定语从句的主从复合句，先行词是book 。