1、it 作形式主语和形式宾语的用法it 作形式主语和形式宾语的用法It 除了用作代词表示指代意义以外，还可以用作形式主语和形式宾语。这种用法是中学阶段英语学习的主要语法项目之一。纵观历届中考题，无论是单项选择、完型填空，还是句型转换或翻译，it 用法始终是反复考查的重、热点之一。现将 it 在特殊句型中作形式主语和形式宾语用法，进行如下归纳分析，以供读者学习和参考。一、 It 用作形式主语1当不定式（短语） 、动名词（短语）或从句在某个句子中作主语时，为保持句子结构前后平衡，避免头重脚轻，因此常用 it 作形式主语置于句首，而将真正的主语放在句尾。此时 it 只起先行引导作用，本身无词义。例如：
2、It is wrong to tell a lie. 说谎是错误的。It is no use arguing about it. 争吵是没用的。It is uncertain who will come. 谁要来还不确定。2It 作形式主语的常见句型 It + be + 形容词 + to do sth. / doing / that .。例如：It is very important to learn a foreign language. 学一门外语非常重要。It is useless crying over the spilt milk. 覆水难收。It was really surpri
3、sing that she married a man like that.她嫁给那样的男士真让人惊讶。 It + be +名词词组 + doing / that .，例如：It is no good telling lies. 撒谎没好处。It is a pity that you didnt go to see the film yesterday. 你昨天没看成那部电影真遗憾。It is a truth that there would be no new China without the Communist Party.没有共产党就没有新中国，这是毋庸质疑的。 It + be + 过
4、去分词 + that .：该句型常见动词有：say, hope, think, suppose, expect, report, know, believe, decide, etc.。例如：It is said that they have invented a new type of computer. 据说他们发明了一种新型电脑。It is believed that China will become one of the strongest countries in the world.大家都相信中国将会步入世界强国之列。It was reported that more than
5、170 thousand people died in the 2004 tsunami.据报道，至少有十七万人在2004年那场海啸中丧生。 It + seems / appears / happens 等不及物动词 + that .。例如：It seems that he enjoys pop songs very much.似乎他非常喜欢流行歌曲。It appears that Tom might change his mind. 看来汤姆可能会改变主意。 若句子是疑问形式，就只能用 it 作形式主语。例如：Does it matter much that they wont come t
6、omorrow? 他们明天不来很重要吗？Is it true that he will go abroad next week? 他下周出国是真的吗？ It + takes + (sb.) + some time + to do sth.这是一个表示“（某人）花多少时间干某事”的句型，其中 it 是形式主语，代替后面的不定式（ to do sth.） ，句型中的 sb.也可以省略。例如：It took me some time to read the reading materials.我花了一些时间才读完那段阅读材料。It took him fourteen hours to go to N
7、ew Zealand from Shanghai by plane.从上海乘飞机去新西兰花了他14小时。How long does it take you to go to Beijing from Qingdao by train?从青岛坐火车到北京一般要花多久时间？I am not sure, but I think it takes at least nine hours to get there.我不能肯定，但估计至少要九个钟头才能到那儿。二、It 用作形式宾语：当不定式（短语） 、动名词（短语）或从句在某个句子中作宾语时，为保持句子结构平衡，避免句式结构的混乱，常用 it 作形式宾语
8、，而将真正的宾语放在句尾。此时 it 仍只起先行引导作用，本身无词义。it 作形式宾语多用于下列句型中。 当不定式（短语） 、动名词（短语）或从句在复合宾语结构中作某些动词的宾语时（如think, make, find, consider, feel, suppose 等） 。例如：They found it pleasant that they worked with us Chinese.他们发现与我们中国人一起工作很愉快。I dont feel it difficult to understand the Special English.我觉得理解英语特别节目并不难。He makes i
9、t a rule never to borrow money. 他立志决不向别人借钱。I think it no need talking about it with them. 我认为没必要跟他们谈。 某些表示“喜、怒、哀、乐 ”的动词，如 like, enjoy, love, hate 等，往往不能直接接宾语从句。例如I dont like it that hes so lazy. 我不喜欢他那么懒惰。I hate it when my mother asks me to eat eggs. 我讨厌母亲要我吃鸡蛋。 that 引导的宾语从句不能直接作介词的宾语。例如：You may dep
10、end on it that we shall always help you.尽管放心，我们会随时帮你的。Would you see to it that she gets home early? 你负责保证她早到家，好吗？He insisted on it that he was innocent. 他坚持说自己是无辜的。 由及物动词与介词组成的固定搭配中，宾语从句若作该动词的宾语时，须借用 it。例如：I leave it to your own judgement whether you should do it.我让你自己判断这事是否该做。We owe it to you that
11、there wasnt a serious accident.多亏了你才没有发生严重事故。考研难度It 作形式主语和形式宾语，虽然是我们高中就学过的语法点，但在考研英语题型中，无论是在阅读还是翻译，常会考查该知识点。一.it 作形式主语。英语中不定式、动名词、主语从句在作主语时主语往往显得很长，使整个句子看上去有点头重脚轻，这样就借助“it”来作形式上的主语，而把真正的主语移到句子后边去，使全句结构上前后平衡。 “it”并无实际意义。It 之后的谓语部分，可以是 be+形容词，be+ 名词(词组) ，或 be+过去分词等。1.不定式做真正主语例句 1： If you are part of t
12、he 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 itll be appropriate for you to make a passing remark about the inedible canteen food or the chairmans notorious bad taste in ties. (2002 Text1)【结构分析】本句包含由 and 连接两个并列分句
13、。第一个分句主干为 you will be in a position，不定式 to know the experiences and problems 做定语，修饰 position，其中 which 引导定语从句，修饰 the experiences and problems。第二个分句为 itll be appropriate for you to ，其中 it 作形式主语，真正的主语为不定式 to make a passing remark about。【参考译文】如果你是你谈话听众中的一员，你就能够了解你们所共有的经历和问题，而且你也可对餐厅极难吃的食物或者领导在选择领带方面差劲的品
14、味进行评头论足。例句 2： Just as on smoking，voices now come from many quarters insisting that the science about global warming is incomplete, that its OK to keep pouring fumes into the air until we know for sure。(2005 Text2)【结构分析】本句的主干是 voices come from，现在分词短语 insisting作 voice 的后置定语，insiste 后接两个 that 引导的宾语从句，分
15、别为 that the science about global warming is incomplete 和 that its OK to keep pouring fumes into the air until we know for sure，第二个 that 从句中，it 是形式主语，真正的主语由不定式短语充当，until we know for sure 为时间状语从句。【参考译文】就像吸烟问题一样，来自不同领域的声音坚持认为有关全球气候变暖的科学资料还不完整。在我们证实这件事之前可以向大气中不断地排放气体。2.主语从句做句子真正主语主语从句做句子真正主语，其结构组成一般是“形式
16、主语 it +谓语+ 关系连词+从句” 。例句 1： Further more，it is obvious that the strength of a countrys economy is directly bound up with the efficiency of its agriculture and industry, and that this in turn rests upon the efforts of scientists and technologists of all kinds. (2000-72)【结构分析】本句主干为 it is obvious that，其
17、中 it 是形式主语，真正的主语为 and 连接的两个 that 引导的名词性从句 that the strength of a countrys economy is和 that this in turn rests。第一个主语从句中，代词 its指代 countrys;第二个主语从句中，this 指代 efficiency of its agriculture and industry。【参考译文】再者，显而易见的是一个国家的经济实力与其工业生产效率密切相关，而效率的提高又有赖于各种科技人员的努力。例句 2： Its not obvious how the capacity to visu
18、alize objects and to figure out numerical patterns suits one to answer questions that have eluded some of the best poets and philosophers。(2007Text2)【结构分析】本句中 It 为形式主语，真正主语是其后 how 引导的主语从句，how the capacity suits one to answer questions，两个不定式结构 to作capacity 的后置定语， questions 后面的 that 引导定语从句，关系代词 that 在从
19、句中作主语。【参考译文】人们非常不清楚的是：(智商考试)这种在心里想象物体的形状或数字模式的能力，怎么能回答一些已经困惑了最优秀的诗人和哲学家多年的问题呢?3. 动名词做真正主语这类句子常见结构为 Its +n.(名词或名词短语)/adj.(形容词)+ doing sth.。1)下列形容词后常用动名词作真正主语：nice, good, useless, hard, foolish, enjoyable, worthwhile 等。例如：形式主语与实际主语形式宾语与实际宾语2)下列名词或名词短语作表语时常用动名词作真正主语：use, good, fun, a waste of, job, tas
20、k 等。例如：Its a waste of time doing this. 这样做是浪费时间的。Its no good /use doing that. 那样做没好处 (没用) 。二.it 作形式宾语不定式、动名词或从句在句中做宾语时，由于该宾语成分过长，为保持句子平衡，常使用 it 做形式宾语，将真正宾语置于句后。这时， it 也无实际意义。这种情况通常只用于能带以名词或形容词作宾语补语的动词后面，比如 think，make，find，consider，feel，suppose 等。例句 1： The explanation for insensitivity to smell seems
21、 to be that the brain finds it inefficient to keep all smell receptors working all the time but can create new receptors if necessary。(2005 完形)【结构分析】本句的主干为主系表结构 The explanationseems to be，表语部分由 that 引导的表语从句充当。在此从句中，使用了 find it +adj.+to do 结构，it 是形式宾语，真正的宾语由不定式短语充当。 but 并列了 the brain 后的两个谓语 finds it inefficient to keep和 can create new receptors if necessary。【参考译文】对气味的不敏感似乎可以这样解释，大脑发现让所有的气味感觉器官一直工作效率会很低，但在需要的时候仍可以创造新的感觉器官。
