it考点讲义：it用作形式宾语、主语的用法知识点归纳2- 高考英语语法二轮复习专题.docx
高中英语语法 高考二轮复习it考点讲义【精讲版】it用作形式宾语、主语的用法知识点归纳it用作形式主语的用法 一、基本用法当不定式、动名词、从句等用作主语时，避免头重脚轻，通常在句首使用形式主语it，而把真正的主语放在句子末尾：Is it necessary to tell his father everything? 有必要把这一切都告诉他父亲吗?Its no good sitting up too late. 熬夜没有好处。It is quite clear that he has read the book. 很显然，他读过这本书。It doesnt matter what he says. 他说什么没关系。 二、几种特殊的形式主语(1) 用作动词look, seem, appear, happen, occur, follow等的主语(后接that从句或as if从句)：It seems as if it is going to rain. 看来要下雨了。It seems that he knows everything. 他好像什么都知道。It (so) happened that I had no money with me. 碰巧我没带钱。From this witness it follows that he must be guilty. 根据该证人的证词判断，他一定有罪。(2) 当系表结构后接有if 或when引出的状语从句时，通常在系表结构前使用形式主语表示说话人对某情况的看法： It was a great surprise to me when he did a thing like that. 他这样做使我很吃惊。It would be a tragedy if anything went wrong. 如果出了什么事就是一个悲剧。(3) 用于其他固定句型，如if it were not for(若不是因为)，its time that(该了)等。 三、误用形式主语的几种情形(1) 在该用it作形式主语的地方而误用其他词：Is _ necessary to tell his father everything?A. it B. thatC. what D. he此题的正确答案应是A(it用作形式主语)，而不能选D。(2) 在不该用形式主语的地方而误用形式主语：_ must be something wrong with the machine.A. There B. ItC. He D. That此题应选A，为there be句型与情态动词must连用的情形。比较以下两组句子：_ is known to us all, the earth turns around the sun._ is known to us all that the earth turns around the sun.A. It B. WhichC. As D. That前一句填C，as用以引导一个非限制性定语从句；后一句填A，it为形式主语，真正的主语是其后的that从句。_ is difficult to persuade her to stay._ is difficult is to persuade her to stay.A. It B. WhatC. He D. That前一句填A，it为形式主语；后一句填B，what用以引导主语从句。注意后一句比前一句在不定式前多了个is。it用作形式宾语的用法 一、基本用法 当不定式、动名词、从句等复杂成分用作宾语且其后跟有宾语补足语时，通常会在宾语补足语前使用形式宾语it，而将真正的宾语移至句末，其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”：I find it difficult to do the job well. 我发现做好这件事不容易。I think it best that you should stay here. 我认为你最好住这儿。We think it no use complaining. 我们认为抱怨是没有用的。 二、几种特殊的形式宾语通常意义的形式宾语主要见于真正宾语为不定式、动名词、从句等且其后跟有宾语补足语时的情形，即用于“动词+it+宾语补足语+真正的宾语”这样的结构，但以下几类形式宾语却比较特殊，其后没有宾语补足语。 1. 动词+ it + that-从句I like it that you came. 你来了，我很高兴。I take it (that) he will come on time. 我认为他会准时来的。You can put it that it was arranged before. 你可以说这是以前安排的。Rumor has it that the defence minister will soon resign. 据传闻，国防部长不久就要辞职。【注】能用于此结构的动词不多，常见的有 have, take, put, like 等。2. 动词 + it + when (if)-从句I dislike it when you whistle. 我不爱听你吹口哨。We really appreciate it when she offered to help. 她来帮忙了，我们十分感激。Id prefer it if I didnt have to do so much work. 要是我不必做那么多工作，好就太好了。【注】能用于此结构的动词不多，常见的有 enjoy, hate, love, like, dislike, appreciate, prefer 等。3. 动词 + prep + it + that-从句See to it that youre not late again. 注意千万不要再迟到。Look to it that this doesnt happen again. 注意不要再发生这种事。I cant answer for it that he will come. 我不能保证他会来。You may rely on it that hell come to meet you. 你放心，他会来接你的。【注】能用于此结构的动词不多，常见的有see to, look to, insist on, stick to, depend on, answer for 等。 4. 动词 + it + 介词短语+ that-从句I owe it to you that I am still alive. 多亏有你我才仍然活着。I took it for granted that he would help us. 我认为他会帮助我们的。【注】能用于此结构的动词不多，常见的有take it for granted, bring it to sbs attention, owe it to sb 等。学科网（北京）股份有限公司
