it的用法.ppt

高考一轮复习高考一轮复习1. it 用作代词用作代词2. it 的常见句型的常见句型（用作形式主语、形式宾语）（用作形式主语、形式宾语）3. it 用于强调句型用于强调句型一、一、it it 作代词作代词1.用作人称代词,代替前文提到的事物My watch is missing. I cant find it anywhere2.2.代替指示代词代替指示代词this, that。 Whats this? Its a computer 3. 表示时间、天气、日期、距离、价表示时间、天气、日期、距离、价值、度量、温度、环境、季节、明暗值、度量、温度、环境、季节、明暗等。等。It is a lovely day, isnt it?(天气天气)1. 作形式主语作形式主语, 代替由不定式代替由不定式, 动名词动名词或从句表示的真正主语。或从句表示的真正主语。 it 做形式主做形式主语的常用句型语的常用句型:二、二、it的常见句型的常见句型It is /was + adj.+for/of sb.to do sth. It was difficult for her to move so heavy a box.Its impolite of you to speak with your mouth full.It is /was + adj.+ that.It was clear that he was lying to us.It is clear (obvious，true, possible，certain) thatIt is important (necessary，right， strange，natural)that 掌握本句型，应该记住所列举的形容掌握本句型，应该记住所列举的形容词，并且记住词，并且记住that后的从句应用后的从句应用虚拟语虚拟语气气 (should+动词原形动词原形)，should可以省可以省去去。=It is important for us to learn English well. .It is + Ved + that.It is said that Tom has come back from abroad.可用于此句型的过去分词常见的有：可用于此句型的过去分词常见的有：said, reported, known, told, believed,hoped,announced,expected,suggested等等。= Tom is said to have come back from abroad.It is important that we (should) learn English well.注意：本句型中的过去分词如果是表注意：本句型中的过去分词如果是表示请求、建议、命令示请求、建议、命令(suggested, ordered, required, proposed, demanded, requested, insisted)等词，等词，that后的从句要用后的从句要用虚拟语气虚拟语气(should十十动词原形动词原形)，should可以省略可以省略。常译为。常译为“据建议；有命令据建议；有命令”。It is suggested that we (should) hold a meeting next week. It is useless/no use/no good It is useless/no use/no good + + _ sth sth. . Its no good arguing with him.Its no good arguing with him. It be +名词词组名词词组+that 从句或不定式从句或不定式It be +a pity, a wonder, an honour,a good thing, a fact, a surprise, good news等等+从句从句Its a fact that he failed the exam.Its an honor for me to work with you.doingIt +be+It +be+时间时间+since +since 从句从句 It 引导的时间句型引导的时间句型 It is two years since he came to work in this city.It was 15 years since he had lived in Shanghai.自从自从.以来已有（时间）以来已有（时间） It +be+It +be+时间时间+before +before 从句从句 It was four hours before the fire was put out. 四个小时后四个小时后大火大火才才被扑灭。被扑灭。It wont be long before we meet again.我们我们不久就会不久就会见面的。见面的。 It is +时间时间+when 从句从句当当的时候是的时候是时间了时间了It was midnight when I got back home yesterday.昨天我回到家里已经是半夜了。昨天我回到家里已经是半夜了。It /This /That +be+ the first (second, third) time that-clause (注注意从句中的时态意从句中的时态) It is the first time that the foreigners have visited the Great Wall.It was the third time that I had done the cooking. It is (high/about) time (that) 主主 语语_ _ / _ sth.Its high time (that) we handed/should hand in our exercise books.shoulddodid完成时态2. It 2. It 作形式宾语的句型作形式宾语的句型 主语谓语主语谓语(feel,make,think,consider，know, find,suppose等）等）+ it +adj./n.+ to do sth. / doing sth./ that-clause1.We consider it a great honor to be able to host the 2008 Olympic Games.2.I found it no use crying for help.3.He has made it clear that we must hand in our papers at the end of this week.主语主语+谓语（谓语（ love，like, hate, mind等等)+ it +that /when 从句从句I dont like it when you shout at me.I mind it when people read my diary without my permission.我介意别人不经我的允许看我的日记。3.其他It的句型 It takes /took /will take sb some time to do sth 做某事花费某人多长时间做某事花费某人多长时间 It seems/seemed/appears/appeared that. 似乎似乎. It looks/looked/appears/appeared as if 看起来好像看起来好像 It happened that 碰巧碰巧. It is up to sb to do sth. 该由某人做该由某人做 It turns /turned out that 原来是原来是. It occurs/ occurred to sb that. 某人突然想起某人突然想起. It doesnt matter / makes no difference whether 某事发不发生都无所谓某事发不发生都无所谓21. It is (just) like sb to do sth 某人某人(恰恰恰恰)是是样子样子” 22. It is a waste of time/money to do sth 做做. 是浪费时间或钱是浪费时间或钱23. It is ones turn to do sth 轮到某人做某事了轮到某人做某事了24. If it were not (had not been) for. 要不是要不是.三、三、it it 用于强调句型用于强调句型1. It iswas+ _+ thatwho句型。句型。被强调的部分（通常是句子的主语、被强调的部分（通常是句子的主语、状语、宾语或宾语补足语）放在状语、宾语或宾语补足语）放在iswas的后面，如被强调的是人，强调的后面，如被强调的是人，强调主主语语可用可用who，强调，强调宾语宾语也可用也可用whom或或who等代替。等代替。 被强调部分被强调部分He met an old friend in the park yesterday.强调主语强调主语 It was he who/that met an old friend in the park yesterday. 强调宾语强调宾语 It was an old friend that/who he met in the park yesterday. He met an old friend in the park yesterday.It was in the park that he met an old friend yesterday.强调地点状语强调地点状语 强调时间状语强调时间状语 It was yesterday that he met an old friend in the park.2. 用助动词用助动词do, does或或did来强调谓语来强调谓语动词。动词。 Do come early tomorrow. He did send you a letter last week. 3. Tom studies hard. 1. Come early tomorrow.2. He sent you a letter last week. Tom does study hard. 3强调句与近似句型的判断强调句与近似句型的判断 如果把如果把“It is (was).that/who ”去掉，去掉，句子意思完整，不缺任何句子成分，句子意思完整，不缺任何句子成分，那便是强调句型。那便是强调句型。区分下例两句：区分下例两句：It was 7 oclock when he came back. It was at 7 oclock that he came back. 他回来时他回来时7点钟了点钟了 . 他是他是7点钟回来的。点钟回来的。 Exercises:1) It was two hours _ he came back.before2) It was two hours later _ he came back.that3) It was two oclock _ he came back.4) It was at two oclock _ he came back.whenthat5) It is two years _ we met him last.since6) It is in three days _ he will know the result.that7) It was the theatre _ Lincoln was murdered.where8) It is a question _ we can collect enough money.whether4. It iswasthat强调句型的被强强调句型的被强调部分如果是调部分如果是原因状语原因状语从句，只能由从句，只能由because引导，引导，不能不能由由since、as或或why引导引导。 It was because the water had risen that they could not cross the river. 正是由于水涨了，他们没有渡过河正是由于水涨了，他们没有渡过河去。去。 5.注意注意 not . until 强调句型的变化。强调句型的变化。 She didnt remember her appointment with the doctor until she had arrived home.It was not until she had arrived home that she remembered her appointment with the doctor.Not until she had arrived home did she remember her appointment with the doctor.It is /was not until + 被强调部分被强调部分+ that+其他成分其他成分.6. 如果强调的是特殊疑问句，要用如果强调的是特殊疑问句，要用“特特殊疑问词殊疑问词+is/was + it + that +”结构结构, 表表示示“究竟是谁究竟是谁，到底在哪里，到底在哪里”等等。等等。 Who was it that you want to see? Where was it that you saw the teacher? Why is it that you want to change your mind? 你究竟为什么要改变主意？你究竟为什么要改变主意？ 7. 强调句的一般疑问句只需把强调句的一般疑问句只需把is/was 提前，反意疑问句也只用对提前，反意疑问句也只用对it is/was 部分进行反意疑问。部分进行反意疑问。Was it in 1939 that the Second World War broke out?It is her that I met yesterday, isnt it?强调句型五注意1.1. 句首词用句首词用“It”, It”, 不能用不能用“This, That”This, That”等。等。2.2. bebe动词总用单数形式，即动词总用单数形式，即isis或或was,was,不能用复数不能用复数形式形式are are 或或werewere。3.3. 连接词一般用连接词一般用that,that,当强调部分是人时，强调主语当强调部分是人时，强调主语也可用也可用who,who,强调宾语也可用强调宾语也可用whomwhom或或whowho。特。特别注意当强调部分是时间状语或地点状语时，不别注意当强调部分是时间状语或地点状语时，不能用能用whenwhen或或wherewhere。4.4. 强调句不能强调句子的谓语部分。强调谓语动词强调句不能强调句子的谓语部分。强调谓语动词时在动词原形前加助动词时在动词原形前加助动词do,does,diddo,does,did。5.5. 如果强调部分是主语时，要注意主谓一致。如果强调部分是主语时，要注意主谓一致。 It was he It was he as well asas well as his parents his parents who/that who/that isis to make the decision. to make the decision. It is It is eithereither you you oror I who/that I who/that amam wrong. wrong.Exercises:1. It _ Mike and Mary who helped the old man several days ago .A. was B. are C. were D. had beenI. Fill in the blanks2. It was not until 1920 _ regular radio broadcasts began.A.which B. whenC. that D. since3. She said she would go and she _ go.A. didnt B. did C. really D. would4. It was the training _ he had as a young man _ made him such a good engineer.A. what; that B. that; what C. that; which D. which; that5. - Were all three people in the car injured in theaccident?- No, _ only the two passengers who got hurt.A. there were B. it were C. there was D. it wasII II句型转换句型转换, ,改写下列各句。改写下列各句。1. Bill made a kite at school yesterday.2. The mother loves her baby dearly.It was Bill who made a kite at school yesterday.The mother does love her baby dearly.3. I painted the door white.It was white that I painted the door.4. She left her gloves in your room.5. Mr. Smith gave a new pen to me.It was in your room that she left her gloves.It was me that Mr. Smith gave a pen to.III用用It相关句型翻译下列句子。相关句型翻译下列句子。1. 我花了将近一个小时整理我的卧室。我花了将近一个小时整理我的卧室。2. 看来今晚我们得挨饿了。看来今晚我们得挨饿了。3. 好像没有人能说服他和我们一起参加比赛。好像没有人能说服他和我们一起参加比赛。4. 当事故发生时碰巧来了位医生。当事故发生时碰巧来了位医生。5. 他就是这样的一个人，把工作推给别人。他就是这样的一个人，把工作推给别人。6. 得由我让他们工作起来。得由我让他们工作起来。7. 原来他根本不在那儿。原来他根本不在那儿。8. 我突然想起我把钱包落在银行了。我突然想起我把钱包落在银行了。9. 他愿不愿帮我们都没什么关系。他愿不愿帮我们都没什么关系。10.玩电游是浪费时间。玩电游是浪费时间。11. 轮到你搞卫生了。轮到你搞卫生了。12. 要不是那块木板，那女孩就淹死了。要不是那块木板，那女孩就淹死了。13. 要我按时完成这个任务是很困难的。要我按时完成这个任务是很困难的。14. 人们希望这座桥能在年底之前完工。人们希望这座桥能在年底之前完工。15. 只是一味地谈论发生在大街上的那场只是一味地谈论发生在大街上的那场 事故是毫无好处的。事故是毫无好处的。16. 还要过多久我们才能再见面？还要过多久我们才能再见面？17. 当我们完成工作时已经是第二天的早上了。当我们完成工作时已经是第二天的早上了。18. 老师规定学生要按时上交作业。老师规定学生要按时上交作业。 (it 作形式宾语作形式宾语)1. It took me nearly one hour to tidy my bedroom.答案：答案：2. It looks as if we have to go hungry tonight.3. It seems that nobody can persuade him to join us in the competition./ Nobody seems to be able to persuade him to join us in the competition.4. It happened that a doctor came to the spot when the accident happened./ A doctor happened to come to the spot when the accident happened.5. Its like him to leave the work to others.6. It is up to me to get all of them working.7. It turned out that he was never there.8. It occurred to me that I had left my wallet in the bank.9. It doesnt matter whether he would help us.10. Its a waste of time to play computer games.11. Its your turn to do the cleaning.12. If it had not been for the block of wood (= But for the block of wood), the girl would have been drowned.13. Its difficult for me to finish the task on time.14. Its hoped that the bridge will have been completed by the end of this year. =The bridge is hoped to have been completed by the end of this year.15. Its no good just talking about the accident that has happened in the street.16. How long will it be before we meet again?17. It was early the next morning when we finished the work.18. The teacher makes it a rule for the students to hand in their exercises on time.