考研英语之小身材大作用的‘it’ 助你备考成功的，考研 it’是英语中常用的词汇之一，大多数人一看到它先想到的是“代词”这个概念，而且通常是指示代词、人称代词和非人称代词，例如：‘My friend bought me a hat and I love it!’‘-Who’s there? -It’s me.’和‘It’s raining outside.’，在这三个句子里‘it’分别指代了‘hat’，人和天气，这些都是‘it’在词汇方面的作用。
除了词汇方面，‘it’在语法中也有很重要的地位，日常常用的句型中就经常出现它，例如：‘It is important for you to have classes on time.’或者‘It’s too late for you to participate the meeting.’等等。实际上，‘it’在语法中的重要作用之一主要体现在它可以代替过长的主语或宾语在句子中充当形式主语或形式宾语，它还可以出现在在强调句中引导强调句型。那么‘it’在考研英语中是怎么考的呢？
就这样走走停停
一、‘it’充当形式主语
在考研英语中出现的很多句子结构比较复杂或者字数很多，在这种句子有时主语会非常长，如果按照“主语 谓语 宾语”的正常语序来书写会出现“头重脚轻”的情况。在英语句法规则中，一般把比较长、比较复杂的部分放在后面，所以如果主语很长的情况下就可以用‘it’代替真正的主语放在句首，而把真正的主语部分放在宾语后面。
在考研英语的长难句中常见的充当主语成分的有动名词短语、to do不定式短语和主语从句，这些句子出现‘it’引导的形式主语的可能性大。在考研英语中常见的形式主语的句型就有如下几类：
（1）it is adj./过去分词 to do sth./从句（that从句常见）
1. Itis difficult to the point of impossibility for the average reader under the age of forty toimagine a time when high-quality arts criticism could be found in most big-city newspaper.(2010 Text 1)

2. If you are part of the group which you are addressing,you will be in a position to know the experiences and problems which are common to all of you and it'll be appropriate for you to make a passing remark about the inedible canteen food or the chairman's notorious bad taste in ties.(2002 Text 1)
3.When I decided to quit my full time employment it never occurred to me that I might become a part of a new international trend.(2001 Text 5)
（2）it is 动词短语 to do sth./从句（that从句常见）
1.If you add to this the effects of a sonar set mounted in the small nose of a torpedo rushing through the water at speeds up to 80 miles per hour with its consequent noise and vibration, plus bullhorn vibrations from the power plant, itcan be seen that only the most advanced electronic filtering gives any chance of success.
（3）it is 不及物动词 从句（that常见）
Thusitfollowsthatthere must be many kinds of mammals, birds, insects of which we know nothing.