接下来我们来看看it在句子中的各种用法。
【形式主语】it常置于句首充当形式主语,真正的主语放在句子后面,如不定式、动名词、主语从句等。
①不定式与动名词:不定式居多,动名词通常为固定的少数几个用法。
【例1】It would be a pity to miss this opportunity.
【理解】真正的主语是不定式短语to miss this opportunity,实际为To miss this opportunity would be a pity.(通常不用不定式作为语法上的主语,大多使用it代替)
【例2】It took me three hours to clean the house.
【理解】真正的主语是to clean the house,此句为固定搭配It takes/took/will take sb. some time to do sth.
【例3】It's no good standing here in the cold.Let's go home.
【理解】真正的主语是standing here in the cold,实际为Standing here in the cold is no good.此句已演化为固定搭配It's no good doing sth.
【例4】It's useless crying over the spilt milk.
【理解】真正的主语是crying over the spilt milk,同样作为固定搭配使用。
②主语从句:共有四种常见句式。
【句式一】It is+n.+that-clause.(is随时态改变而改变,我就不打斜杠加上was之类的了)
【例】It is a great pity that he cannot come.
【理解】真正的主语是that he cannot come。
【句式二】It is+adj.+that-clause.
【例】It is strange that he should know nothing about it.
【理解】真正的主语是that he should know nothing about it。这里的should具有强烈的情感意味,翻译为“竟然”。
【句式三】It + v. (+宾语+状语)+主从.(括号中的宾语、状语属于动词的宾语或状语,根据具体情况决定)
【例1】It pleases me that he should want to talk to me.
【理解】真正的主语是that he should want to talk to me,全句翻译为,他竟然愿意和我交谈,这让我很高兴。
【例2】It doesn't matter much where we live.
【理解】真正的主语是where we live,不要僵化思维认为只能由that引导主从了。此句中much作为matter的状语,全句翻译为:我们住在哪里并不重要。
【句式四】It be done +主从.(常用whether/who等特殊疑问词转化来的连接词引导)
【例】It is not decided who will take charge of the program.
【理解】真正的主语是who will take charge of the program。
【总结】it作形主,非谓语动词是真正的主语时,大多为动词不定式。
用动名词的基本都是固定搭配:no good、no use、useless、useful、fun、a waste of time/energy/money作表语时用动名词doing形式。It is … doing sth.
主语从句中句式一中的常见名词还有:a fact,a shame,no wonder
句式三中常见的动词有:seem,appear,turn out,occur to (sb.)注意时态变化
句式四中常见考查多为be decided