一、it 的基本用法

　　1. 作人称代词

　　(1)代替前面(或后面)的单数名词或分句等所表示的事物。

　　①Although we can not see it, there is air all around us. ( it 指代后文的air)

　　尽管我们看不到空气，但它却包围着我们。

　　②They said they had finished the work, but I can't believe it.(it指代前一分句)

　　(2) 代替有生命但不能或不必分阴阳性的东西(包括婴儿)。

　　①Yesterday we saw a big camel. It was about 3 metres high.(it指代camel)

　　昨天我们见到一头大骆驼。它大概有3米高。

　　②When a baby is crying, it may be hungry.(it 指代baby)

　　当婴儿啼哭时，它可能是饿了。

　　(3) 在某些习惯说法中it 可指代人。(前提是说话者双方都知道是somebody)

　　A: Someone is knocking at the door? 有人在敲门吗？

　　B: Really ? Who is it? 真的？是谁呢？

　　C: It’s me. 是我。

　　(4) 指环境情况(天气、时间、距离、度量衡等)

　　① It is five kilometres from the office to my home.

　　从办公室到我家有5公里。

　　② It often rains in summer. 夏天经常下雨。

　　2. 构成强调结构

　　it用以帮助改变句子结构，使句子的某一成分受到强调。形成“It is (was) ＋所强调的成分(主语、宾语、状语)＋that(或who, whom)＋其它成分。”在这个 句型中，it本身没有意义。

　　It was in Shanghai that I saw the film. (强调地点状语)

　　我是在上海看的这部电影。

　　3. 作形式主语或宾语

　　为使句子平衡，非谓语动词或从句作主语或宾语时，通常用it作形式主语或宾语，而将真正的主语或宾语置于句末。

　　It is not easy to finish the work in two days.

　　两天内完成这项工作并非易事。

　　4. 用在一些固定句型或搭配中，it没有实在意义，但不可省略。

　　Does it matter if he can’t attend our party ?

　　如果他不能参加我们的聚会，会有什么问题吗？

　　在学习代词it 的用法时要搞好以下两个区别：

　　二、 it与one的区别

　　两个词都可代表前面提到的名词，但it用于同名同物的场合；one则用于同名异物的场合。

　　①─ Do you still have the bicycle? 你还有自行车吗？

　　─ No, I have sold it. 没了，我已经把它卖了。(it指上文的the bicycle)

　　②─ Is this knife yours? 这是你的吗刀？

　　─ No It’s Xiao Zhang’s .Mine is the one on the desk. 不是。这是小张的。我的是桌子上的那个。(one 指代knife, 但the one并不是上文的this knife)

　　三、 it 与that的区别

　　两词都可代替某一特定名词。但that指同一类，并非同一个。

　　①The climate of South China is mild; I like it very much. ( it 指the climate of South China)

　　华南的气候很温和，我非常喜欢。

　　②The climate of South China is better than that of Japan. 华南的气候比日本的要好。( that 指the climate,但并不是指the climate of South China)

　　直击高考

　　1. —There’s coffee and tea: you can have .

　　—Thanks. (NMET2003)

　　A. either B. each C. oneD. it

　　2. It was about 600 years ago ____the first clock with a face and an hour hand was made. (NMET1997 )

　　A. that B. until C. before D. when

　　3. Was ____ that I saw last night at the concert? (1997上海)

　　A. it you B. not you C. you D. that yourself

　　4. ____ was in 1979 ____ I graduated from the university. (1998上海)

　　A. That; that B. It; that C. That; when D. It; when

　　5. I hate____ when people talk with their mouths full. (NMET1998 )

　　A. it B. that C. these D. them

　　6. _____is a fact that English is being accepted as an international language.(NMET1995)

　　A. There B. This C. That D. It

　　7. It is the ability to do the job ____matters not where you come from or what you are. (NMET 2000)

　　A. one B. that C. what D. it

　　答案与分析

　　1. A本题考查代词的用法。A、B、C三项均可作不定代词：either指二者中任何一个；each指两者或两者以上之中的每个人或每个物；one用来代替上文出现过的单数可数名词，泛指一个；D项it用作人称代词时，用来指代上文提过的某个事物。前句叙述了有咖啡和茶,根据常理，只能是二者之中选一种，故答案为A。

　　2. A 在强调结构中，强调的时间状语。在本题中it无所指。

　　3. A 该题是强调句式的疑问句形式，意思是“昨天晚上我在音乐会上见到的是你吗？”

　　例如：When did you come back? 强调句式：When was it that you came beck? 即：疑问副词加上强调句的一般疑问句。

　　4. B 该题考查对英语强调句式的掌握。从in 1979我们就可以判断本句强调状语。

　　5. A it是代词作宾语，指代“people talk with their mouths full ”这件事。

　　6. D it是形式主语，that从句作真正主语。

　　7. B 此题中一个非常关键的词是 “matters”，此词为动词的谓语形式，故此题不是一个简单句，该句又不是名词性从句，故A、C、D均可排除，B项可构成强调句型，对主语进行强调。

　　专项训练

　　1. Is___necessary to complete the design before National Day ?

　　A. he B. it C. that D. this

　　2. ─Is it going to snow tonight?

　　─ I’m afraid___.

　　A. it B. that C. so D. this

　　3. Does____matter if he can’t finish the job on time?

　　A. this B. that C. he D. it

　　4. ─Do you have my pen, Mary?

　　─Yes, I have ___right here.

　　A. one B. it C. this D. that

　　5. I found ___impossible for ____to work out the maths problem.

　　A. it; he B. that; he C. that; him D. it; him

　　6. ____is____who wants to see you.

　　A. It; he B. That; he C. It; I D. That; him

　　7. Where was ____that you were born?

　　A. 不填 B. its C. it D. you

　　8. ─Who’s knocking at the door?

　　─____me.

　　A. That’s B. This is C. He’s D. It’s

　　9. ____that you are here.

　　A.I am so great a pleasure B.I am such great pleasure

　　C. It’s so great a pleasure D. It’s so great pleasure

　　10. We consider ____ a beautiful city to visit in autumn.

　　A. that B. it C. this D. what

　　11. In which play is ____your brother appears ?

　　A. that where B. this when C. it that D. it where

　　12. ____the harder you work, the better result you'll get.

　　A. It’s believed that B. What we believe that

　　C. It’s fact that D. What the fact is

　　13. ─What’s wrong with the computer?

　　─I don’t know.____.

　　A. The computer won’t work B. It simply doesn’t work

　　C. That mustn’t work D. It simply won’t work

　　14. You promised to write the article, so you must____.

　　A. do writing B. do writing it C. write an article D. do it

　　15. ____is a pity that you forgot both her address and her telephone number.

　　A. That B. This C. It D. There

　　16. I was disappointed with the film. I had expected ____ to be much better.

　　A. that B. this C. one D. it

　　17. Nothing can stop us,___?

　　A. can’t it B. can it C. can’t we D. can we

　　18. Teacher had told him again and again not to read such books , but ___ didn’t help.

　　A. he B. they C. she D. it

　　19. He said:“___a long way to school. ____a long way to go yet before we arrive.”

　　A. It is; There is B. There is; It is C. It is; It is D. There is; There is

　　20. ____needs further discussion whether we’ll build a library or not.

　　A. We B. He C. It D. The thing

　　答案与分析

　　1. B it作形式主语，真正的主语为 to complete the design before National Day。

　　2. C本空极易错选 A。afraid为形容词，后面不能直接跟名词或代词作宾语。so在本句中指代上文中的观点。

　　3. D matter作动词时，在疑问句或否定句中用it作主语，然后把whether引导的从句位于句末。

　　4. B 此题极易错选 A。one相当于a pen。根据上下文，本句中的it 指代上文中的 my pen,因此为特指。

　　5. D it为形式宾语，后面的for him to work out the maths problem为真正的主语。

　　6. A It is...who...为强调结构，C有一定干扰性，从本句的谓语wants看，C不合题意。

　　7. C 解析本句，我们最好把它还原为陈述句;I was born in Tianjin, 然后再用强调句强调地点状语；It was in Tianjin that I was born, 最后我们再对 in Tianjin进行提问。

　　8. D it在口语中可以指人。

　　9. C it 作形式主语，真正的主语为that you are here。D 有一定干扰性， 作“ 趣事”讲pleasure是可数名词。

　　10. B 在本句中it并非形式宾语。分析本句我们可以得出， 本句承接上文而来，it指代上文提到的那个城市。

　　11. C本题与第7题有些相似，it is...that 都是用在强调句中，第7 题被强调的部分是where,而本题被强调部分是in which play。

　　12. A It’s believed that为固定搭配，意思是“据人们相信”，其中it为形式主语，真正的主语为that 从句。与此类似的搭配还有：

　　It is said that...据说……

　　It is reported that...据报道……

　　It is known that...众所周知……

　　13.B 第二次提到the computer, 因此用it。A ,D均有一定干扰性，第二个说话者叙述the computer现在的状况，因此时态应为一般现在时。

　　14. D do it指 write the article, C 属于冠词使用错误。

　　15. C It is a pity that为固定搭配，意思是“太可惜了”，其中it 是形式主语。

　　16. D it 特指the film。C 有一定干扰性。one 在此等于a film。

　　17. B本句的主语是nothing, 第二次提到 nothing, anything, everything , this, that,用it。在本句中 it 相当于anything。

　　18. D it 指代Teacher had told him again and again not to read such books。A, C有较大干扰性，在这里说话人并非指teacher帮不上忙，而是指这句话(或这件事)根本不起作用。

　　19. A第一空 “it” 指距离，第二空“there be”表示“存在”。

　　20. C it为形式主语，真正的主语为whether 引导的从句。D 有一定干扰性。 若用 The thing 作主语，放在句末的whether从句则多余。