1、高中英语牛津上海版高中二年级第一学期It的用法讲解及练习有答案It的用法讲解及练习1、it可指天气、温度、时间、距离等e.g.It is cold today, isnt it?2、用作人称代词，代替前文提到过的事物e.g. The dog is not a cold-blooded animals. It doesnt need to hibernate.3、为避免重复，it可用来代替前面说过的短语或句子e.g. I tried to persuade my father to give up smoking, but found it impossible. (it=to persuade
2、 my father to give up smoking)4、代替指示代词this，thate.g.Whats this?Its an album.Whose new bike is that?Its Marys.【注】it与one，that的区别it=the(this, that)+名词，特指并且代替前面所提到的某特定事物。e.g. Hes bought a new car, so he drives it everywhere to show it off.one=a+名词，one指前面提到的同类事物中的不同的另一个。e.g. He needs a computer, but he ca
3、nt afford one.that=the+名词，that指代的名词与前面的名词属于同一类，但不属同一个。e.g. The population of China is larger than that of Japan.(注意：that指代population，但其后有一个of短语作定语，以区别于the population of China)【注】it与that的异同it指同一事物，that指同类但并不是同一事物e.g. I like the climate of Kunming more thanthatof Beijing. The climate of Kunming is mil
4、d, and I likeit.5、it作形式主语it在句中可作形式主语，而真正作主语的主语从句需要放在句子的末尾。主语从句后置常用以下几种结构：1）It is/was + adj. + subject-clause可用于此句型的形容词有：clear, certain, funny, good, impossible, likely, natural, obvious, possible, probable, strange, surprising, true, unusual, wonderful等e.g. It is obvious that going for sports will d
5、o a lot of good to your health.2）It + be + adj./n. (for sb./of sb.) + to do sth.该句型中的形容词通常表示事物的特点或特征的，如difficult, hard, easy, impossible, necessary, important等，此时用for；或表示人的性格特征或特点的，如nice, good, bad, kind, silly, foolish, wise, clever, careless, rude, brave, cruel, careful, grateful等，这时要用of3）It is/wa
6、s +名词词组+ subject-clause可用于该结构的名词词组有：a pity/duty, a good thing, no surprise, good news, an honor, a fact, a mystery, a shame, manners等e.g. Its a pity that I didnt attend the party.4）It is/was + V-ed + subject-clause可用于该结构的动词的过去分词有：said, reported, thought, supposed, believed, hoped, expected, known, d
7、ecided, announced, arranged等e.g. It is said that something had been done to end the pollution.(注，本句还可改写为：Something is said to have been done to end the pollution.)5）It + vi. + subject-clause可用于该结构的动词有：appear, seem, happen, occur等e.g. It appeared to scientists that the stars had moved.e.g. It doesnt
8、matter whether hell join the army or not.It makes no difference where we have the conference.6）一些固定句型It takes sb. some time to do sth.e.g. It will take you two days to get there on foot.It costs sb. some money to do sth.e.g. It costs 1,000 dollars to fly to America.It is/was no use(useless) doing（做什
9、么是没有用处的）e.g. Its no use arguing with him.It is/was no good doing（做什么是没有好处的）7）以下句型结构中需要用虚拟语气It is/was important(necessary, strange) that; It is/was ordered(required, suggested, proposed) that; It is/was a pity(a shame) that表示遗憾等感情的句子中，主语从句要用“should+动词原形”，should可以省略。e.g. Its necessary that he (should)
10、 be operated on at once.It is (high) time that结构中用should+动词原形（should不能省略）或动词过去式。e.g. It is high time that you should make(made) full use of your time to go over your lessons.6、it作形式宾语1）动词consider（feel, find, think等）+ it +形容词（名词）+不定式（动词-ing形式，从句）。e.g. She thinks it no use telling me.2）主语+appreciate（e
11、njoy，like，love，hate）+ it + if（when）结构e.g. We would appreciate it if you could come to help us.3）depend on, rely on, see to(负责/设法做到), take for granted(习以为常)等短语后跟that从句时，要以it作形式宾语。e.g. Were depending on it that he will finish the job by Friday.7、强调句中的itIt可以用来改变句子结构，使句子的某一成分得到强调1）强调句的基本句型it is/was +被强调
12、成分+ that/who +其他成分e.g.原句：I told Jim the news in our office yesterday.强调主语：It was I that/who told Jim the news in our office yesterday.强调宾语：It was Jim that I told the news in our office yesterday.(或It was the news that I told Jim in our office yesterday.)强调地点状语：It was in our office that I told Jim th
13、e news yesterday.强调时间状语：It was yesterday that I told Jim the news in our office.2）强调句的一般疑问句型Is/Was + it +所强调部分+ that/who?e.g. Was it you that told Jim the news in your office yesterday?3）强调句的特殊疑问句型疑问词+ is/was + it + that/who?e.g. Who was it that told Jim the news in your office yesterday?【注】强调句与主语从句
14、虽然在形式上很相似，即都含有it is(was)that。但，区别在于：强调句去掉it is(was)that之后，句子结构仍然完整，而主语从句却不能这样。e.g. (It is) our hope (that) the two sides will work towards peace.去掉It isthat之后，句子是不成立的。由此得出该句不是强调句，而是一个简单的主语从句，it是形式主语，从句是真正的主语。8、It引起的几个易混淆的时间句型1）It be +时间+ since-clause这个句型表示从since从句谓语动作发生以后到现在或过去所经过的一段时间，意为“自从以来已多久了”，
15、主句多用一般现在时，从句用一般过去时，如果表示过去的情况，主句一般用过去时，从句用过去完成时，或主句用过去完成时，从句用一般过去时。要注意：since引导时间状语从句时，从句若使用终止性动词，则表示该时间是主句时间段的终点（时间从现在算起）；若从句使用延续性动词，则表示该动作状态的结束（时间从过去算起）。e.g. Its five years since they got married.他们结婚已经5年了。Its five years since they were married.他们离婚已经5年了。Its ten years since his father was a worker.他
16、父亲不当工人已经10年了。I havent seen him since we were boys together.我们长大以后再没有见过面。It is three years since his father passed away.他父亲过世已经3年了。2）It be +时间+ before-clause这个句型中的时间一般为表示一段时间的词语（如：long years, months, weeks, days, hours, minutes），主句中的谓语动词用肯定式，意为“过多长时间才”。主句的谓语动词是否定式时，意为“没过多长时间就”。主句的时态可用过去时was或将来时will b
17、e；用was时，before从句的动词用一般过去时；用will be时，before从句常用一般现在时。e.g. It was not long before she learned those poems by heart.她没过多久就背会了那些诗。It was long before the police arrived.过了很久警察才来。It will be hours before he makes a decision.要过好几个小时他才会作出决定。It will not be hours before we meet again.要不了几个小时我们还会再见面的3）It be +时间
18、+ when-clause这个句型中，it指时间，而且表示时间的词语前没有介词（时间一般是具体时间）。主句和从句中的谓语动词在时态上是一致的，主句是will be，when从句用一般现在时代替将来时。e.g. It was already 8 oclock when we got home. It will be late afternoon when they get there.4）It be +时间+ that-clause这个句型是个强调句型。e.g. It was at 5 oclock that he practiced playing the violin in the morn
19、ing.(原句是：He practiced playing the violin at 5 oclock in the morning.)比较：It was 5 oclock when he started in the morning.（5 oclock前没有介词，这个是定语从句）5）It be + time + that-clause这个句型属虚拟语气结构，不管主句中用的是is或was，that从句都须用动词的过去式或should+动词原形（但不及物动词通常用过去式），在time之前有时可以加上high或about以加强语气。e.g. It is high time (that) he w
20、rote a letter to his girlfriend.It is time (that) we made peoples life a little easier. = It is time that we should make peoples life a little easier.9、It/This/That + be + the first(second, third) time + that-clause这个句型表示截止到说话时为止的某人的一种经历，关键是注意time前有序数词，主句是一般现在时is时，从句要用现在完成时；如果主句用一般过去时was时，则从句须相应地用过去
21、完成时。e.g. This is the first time (that) these Europeans have visited the Great Wall.It was the fifth time (that) I had paid a friendly visit to America.10、在一些相对固定的词组中，没有特殊含义，经常不翻译。e.g. Hes never really made it as an actor.作为演员，他从未获得过真正的成功。 It is my turn.轮到我了。专项练习（一）( ) 1. It was through Xiao Li I got
22、 to know Xiao Wang.A. who B. whom C. how D. that( ) 2. It was in the rice fields we had our league meeting.A. where B. that C. in which D. on which( ) 3. It was on October 1st new China was founded.A. which B. when C. as D. that( ) 4. Was it because he was ill he asked for leave?A. and B. that C. th
23、ats D. so( ) 5. Mary speaks in a low voice; is difficult to know what she is saying.A. it B. that C. so D. she( ) 6. It was I met Mr Green in Shanghai.A. many years that B. many years beforeC. many years ago that D. many years when( ) 7. is not everybody can draw so well.A. It; all B. It; thatC. The
24、re; who D. There; that( ) 8. So that no fish can live in it.A. shallow is the lake B. the lake is shallowC. shallow the lake is D. is the lake shallow( ) 9. was Jane that I saw in the library this morning.A. It B. He C. She D. That( ) 10. Its the third time I have been here.A. that B. when C. after
25、D. who( ) 11. It was simply for that reason I wouldnt tell him the truth.A. why B. which C. so D. that( ) 12. Was it in this place the last emperor died?A. where B. that C. which D. in which( ) 13. It Mike and Mary who helped the old man several days ago.A. was B. were C. are D. had been( ) 14. It w
26、as about 600 years ago the first clock with a face and an hour hand was made.A. that B. until C. before D. when( ) 15. It was not until 1920 regular radio broadcast began.A. while B. which C. that D. since( ) 16. It was not until she came to see us her mother was ill in bed.A. when we knew B. that w
27、e knewC. that did we knew D. that did we know( ) 17. was for his kindness that everyone praised him. A. It B. What C. So D. Such( ) 18. It was because of bad weather the football match had to be put off.A. so B. so that C. why D. that( ) 19. It is these poisonous products can cause the symptoms of t
28、he flu, such as headache and aching muscles.A. who B. that C. how D. what( ) 20. Bills aim is to inform the viewers that cigarette advertising on TV is illegal, ?A. isnt it B. is it C. isnt he D. is heKeys: 1. D 2. B 3. D 4. B 5. A 6. C 7. B 8. A 9. A 10. A 11. D 12. B 13. A 14. A 15. C 16. B 17.A 1
29、8. D 19. B 20. A专项练习（二）( ) 1. It avoid being punished severely that the driver ran away without sending the injured person to the hospital.A. was because B. was toC. was because of D. was about to( ) 2. about his presentation at the meeting that made the audience interested?A. Was it B. When was it
30、C. What was it D. How was it( ) 3. Was it in 1969 the American astronaut succeeded landing on the moon?A. when; on B. that; on C. when; in D. that; in( ) 4. they met each other and became fast friends.A. It was in the lake area in the north of the country whereB. Being in the lake area in the north
31、of the countryC. It was in the lake area in the north of the country thatD. It was in the lake area in the north of the country when( ) 5. The truth is that it is only by studying history learn what to expect in the future.A. can we B. that we canC. and then we can D. so that we can( ) 6. It was courage him to break bricks with his bare hand.A. which B. that has enabled
