while-“it”用法总结共38页课件.ppt

1、知识要点 while的用法(1)引导时间状语从句，意为“当的时候,在期间”从句中的谓语动词应用延续性动词或表示状态的词；(2)引导让步状语从句,多用于句首。意为“尽管,虽然”；(3)While作并列连词用,意思为“而,然而”,表前后意义上的对比；(4)引导条件状语,意思是“只要”；(5)while可用作名词,意为“一会儿;一段时间”。知识要点 while的用法1.Some people waste food while others havent enough.有些人很费粮食，然而有些人却吃不饱。(然而)2.We must strike while the iron is hot.l趁热打铁。

2、(当的时候)3.While there is a way there is away.有志者事竟成。(只要)4.While these experiments are interesting and useful,it is important to remember that they may not always tell us much.虽然这些实验很有趣也有用，但是很重要的是要记住，这些实验也可能不会告诉你很多。(虽然，尽管)返回目录根据句意，辨别while的含义知识要点 while的用法l 5.While there is life there is hope.l只要生命存在，就有希

3、望。(只要)6.While she was listening to the radio,she fell asleep.她听着收音机睡着了。(当的时候)7.The son was having a good meal at home,while the parents were working in the fields.儿子在家吃好饭而父母却在田里辛勤劳作。(然而)8.While he loves his students,he is very strict with them.虽然他爱他的学生，可是他对他们很严格。(虽然，尽管)知识要点 while的用法1.I ought to have

4、 helped her,but I never could.2.Honey is sweet,but the bee stings.3.In some places women are expected to earn money while men work at home and raise their children.4.Some people are wasting water while some people are fighting for water.while表示前后句形成“对比”关系，but只表达转折。根据例句，辨别while与but的区别知识要点 It的用法 （一）作人

5、称代词1、it代替前面（或后面）的单数名词,不可数名词或分句等所表示的事物。You cannot eat your cake but have it.（it代替前面的代替前面的cake）Although we cannot see it,there is air all around us.（it代替后面的代替后面的air）They say he has left town,but I dont believe it.（it代替前面代替前面Theytown分句中的情况）分句中的情况）返回目录知识要点 2、代替有生命但不能或不必分阴阳性的东西（包括婴儿）。Yesterday we saw a b

6、ig tree.It was fully twenty metres high.（it代替前面的代替前面的tree）The baby cried because it was hungry.（it代替前面的代替前面的baby）返回目录知识要点 3、在某些习惯说法中，可以代替人。1)-Someone is knocking at the door,Peter.-Who is it?-Its me.2)-Who are singing?-It is the children.3)-The light is still on in the lab.It must be the third-year

7、students doing the experiment.返回目录知识要点 4、it与one的区别：这两个词都可以代表前面说过的单数名词，但it用于同名同物；one则用于同名异物。It还可以指不可数名词。1)-Do you still have the bicycle?-No,I have sold it.2)-Is this knife yours?-No.It is Xiao Zhangs.Mine is the one on the desk.返回目录知识要点 5、it与that的区别：两词都可代替某一名词(可数或不可数)，that指同一类，it指同一个。The climate of

8、South China is mild(温和的);I like it very much.（it指指the climate of South China）The climate of South China is much better than that of Japan.（that指指the climate）返回目录知识要点 （二）作无人称代词it作无人称代词时，除了句中找不到它所代表的词语外，另一个特点是它后面的内容都是表示天气、时间、距离、度量衡及情况等。It is fine(rainy,windy,etc.).It is noon.It is a half hours walk to

9、 the factory.It is eighteen square metres in area.What does it matter?返回目录(三三)引导词引导词it引导强调句式引导强调句式1.It is+被强调部分被强调部分+that.使用该句型有以下几点请注意：使用该句型有以下几点请注意：强调句的谓语强调句的谓语is或或was永远用单数永远用单数.It was yesterday that I met your father in the street不管被强调部分是哪种状语，只能用不管被强调部分是哪种状语，只能用that连接，不得使用连接，不得使用where、when等连词等连词.

10、It was in the street that I met your father yesterday被强调部分为人时，可用被强调部分为人时，可用who(主格或宾格主格或宾格)和和whom(宾格宾格)代替代替that，用，用that也行。也行。It was your father that/whom/who I met in the street yesterday2)It was I that/who met your father in the street yesterday强调句中强调句中 也要注意主谓一致、人称一致和否定转也要注意主谓一致、人称一致和否定转移的问题。移的问题。It

11、 is they who are our friends1)It was not until ten oclock that we got home last night注意不要混淆强调句和其他从句。It is wasthat为强调句标志，去掉后仍可组成一个完整的句子，只是没被强调,而其他从句一般不具备这一特征。比较：1)It was ten oclock when we got home last night我们昨晚到家时已十点了。2)It was at ten oclock that we got home last night我们昨晚是在十点到家的。要点点拔第一句不是强调句，when不可

12、改为that,因为去掉it was和that后，只能组成“We got home ten oclock last night”这样一个不完整的句子；第二句是强调句，that不可改为when2.It is not until+被强调部分被强调部分+that.该句型也是强调句型。主要用于强凋时间状该句型也是强调句型。主要用于强凋时间状语，译成汉语直到才，可语，译成汉语直到才，可以说是以说是 not.until.的强调形式。的强调形式。It was not until she took off her dark glasses that I realized she was a famous fil

13、m star.=Not until she took off her dark glasses did I realize she was a famous film star.=I didnt realize she was a famous film star until she took off her dark glasses.3.it 用作形式主语用作形式主语3.1 代替主语从句代替主语从句1）It is+adj.+that从句从句 It is clear(obvious，true，possible certain.)that.“清楚（显然，真的，肯定）清楚（显然，真的，肯定）”It

14、 is very clear that hes round and tall like a tree.It is important(necessary，right，strange，natural.)that.that 后的从句中要用虚拟语气（后的从句中要用虚拟语气（should+动词原形），动词原形），should 可以省去，建议记住该句型中的形容词。可以省去，建议记住该句型中的形容词。It is important that we(should)learn English well.2）.It is+v-ed+that 从句从句 It is said(reported，learned.)t

15、hat.据说（据报道，据悉）据说（据报道，据悉）“。It is said that he has come to Beijing.It is suggested(ordered /demanded/insisted/commanded.)that.主句中的过去分词是表示请求，建议，命令等词时，主句中的过去分词是表示请求，建议，命令等词时，that后的从句要用虚拟语气（后的从句要用虚拟语气（should+动词原形），动词原形），should 可以省；常译为可以省；常译为“据建议；有命令）据建议；有命令）It is suggested that the meeting(should)be put

16、off.3）.It is a pity(a shame.)that.that后的从句一般用虚拟语气（后的从句一般用虚拟语气（should+动词原形），动词原形），should可省去表示出乎意料，常译为可省去表示出乎意料，常译为“竟然竟然”。没有。没有这种意义时，则不用虚拟语气。这种意义时，则不用虚拟语气。It is a pity that such a thing(should)happen in your class.It is a pity that he is ill.4).It is time(about time，high time)that.该句型中该句型中that 后的从句应该用

17、虚拟语气，值得注意的是后的从句应该用虚拟语气，值得注意的是常用过去时态表示虚拟常译为是（正是）的时常用过去时态表示虚拟常译为是（正是）的时侯侯 It is time that children went to bed.It is the first(second.)time that.“是第一（二）次是第一（二）次”。It is the first time I have been here.=This is the first time I have been here.5).It happens(seems，looks，appears)that.该句型中该句型中it是形式主语，是形式主语，

18、that 引导的是主语从句，主句引导的是主语从句，主句中的中的happen，seem等词是不及物动词。等词是不及物动词。It happened(so happened)that he met his teacher in the street.碰巧碰巧.It seems that he will be back in a few days.看看来来3.2.作形式主语替代不定式作形式主语替代不定式 1).It takes sb.to do sth.做要花费某人做要花费某人 It took thousands of people many years to build the Great Wall

19、.2).It is kind(of sb.)to do sth.主句中的形容词必须是能表示逻辑主语特征的形容词。主句中的形容词必须是能表示逻辑主语特征的形容词。常见的有：常见的有：bad，brave，careless，clever，cruel，foolish，stupid，wise wrong等。等。这个句型可以改写为：这个句型可以改写为：sb.is kind to do sth.。It is kind of you to say so.=You are kind to say so.3).It is necessary(for sb.)to do sth.常见的形容词有：常见的形容词有：im

20、portant，necessary，natural easy，safe，common，normal，hard，difficult,dangerous，等。等。在在中的形容词作表语可以用从句改写，中的形容词作表语可以用从句改写，如：如：It is important for her to come to the party.=It is important that she(should)come to the party.4).It is such a privilege to do.做做是一份荣幸是一份荣幸 It was is such a privilege to meet Preside

21、nt Obama.It is no good(use)doing sth.该句型中的真正主语是动名词短语，主句中的表该句型中的真正主语是动名词短语，主句中的表语可以是语可以是no good，(not any good)，no use，(not any use)。It is no good learning English without speaking English.Its useless trying to argue with Shylock.3.3.作形式主语替代ing形式 4.It 作形式宾语作形式宾语.We think it important to learn a foreig

22、n language.该句型中的该句型中的it 作形式宾语，为了记忆方便我们可称该句型作形式宾语，为了记忆方便我们可称该句型为为“7123结构结构。7指主句中常用的动词：指主句中常用的动词：think,believe,make,find,consider,feel,suppose；1指的是形式宾语指的是形式宾语it；2指的是宾补的两种形式：形容词或名词；指的是宾补的两种形式：形容词或名词；3指的是真正宾语的三种形式：不定式短语，动名词短语指的是真正宾语的三种形式：不定式短语，动名词短语或或that引导的宾语从句。引导的宾语从句。We think it our duty to clean our

23、 classroom every day.He felt it important learning English well.They found it difficult that they would finish their work in two days.五、特殊句型五、特殊句型1).It is.since.。It is(has been)5 years since his father died.2).It is.when.。“当的时候，是当的时候，是”It was 5 oclock when he came here.3).It be.before.该句型主句中的该句型主句中的

24、 it 指时间，指时间，主句中的时态常是一般将来时或过去主句中的时态常是一般将来时或过去时两种时态主句中的表语多是时两种时态主句中的表语多是long，not long，3 days，2 weeks 等表示时间段的词或短语，常译为等表示时间段的词或短语，常译为“之后之后”。It was 3 days before he went to Beijing.It will be not long before he finishes his job.4）.It looks(seems)as if.该句型中该句型中it无意义，无意义，as if 引导表语从句。常译为，引导表语从句。常译为，“看看起来好象

25、起来好象”如果与事实不相符合，则用虚拟语气。如果与事实不相符合，则用虚拟语气。It looks as if he is ill.（真的病了）（真的病了）It looks as if he were ill.（没有生病）（没有生病）It seemed as if he were dying.5）.It doesnt matter whether(if).该句型中该句型中whether(if)引导的从句是真正主语，该句型常引导的从句是真正主语，该句型常译为不论（是否）没关系。译为不论（是否）没关系。It doesnt matter if they are old.6）Id appreciate i

26、t if Id appreciate it if you can come to my party.7）He made it clear that He made it clear that he would leave the city.8）I hate/like it when I hate it when people shout at me.I like it when people praise me.l9）make it 及时赶到及时赶到;成功成功;办成办成lYou can make it if you hurry.lYou neednt worry;he will make it

27、.l10）catch it 被责骂被责骂;受处罚受处罚lIf I come home late Ill catch it from my mother.lYoull catch it because of your carelessness.l11）.It的一些习惯用法的一些习惯用法lHow is it with your study?学习好吗？学习好吗？lThats it.这就对了。这就对了。lIt went hard with him.他身遇不幸。他身遇不幸。lIt is all over with me.我完蛋了。我完蛋了。lWe must fight it out.我们必须坚持到底。我

28、们必须坚持到底。lI cant help it.我没有办法。我没有办法。l 1.（09四川）I like this house with a beautiful garden in front,but I dont have enough money to buy _.lA.one B.it C.this D.thatl【答案】B。l【解析】意思是：我喜欢这个前面有一个美丽花园的房子，但是我没有足够多的钱去把它买下来。第一句话中的this house表明在该语境中是特指的用法，所以答案为it，表示特指。该题容易误选one，要注意的是one表示泛指。l【考点定位】it/that/one用法区别高

29、考链接高考链接l2.（09浙江）Ive read another book this week.l Well,maybe _ is not how much you read but what you read that counts.lA.this B.that C.there D.itl【答案】Dl【解析】句中“not how much you read but what you read”足以做动词count 的主语，所有选D 使之构成强调句型。l【考点定位】本题考查强调句型和名词性从句。返回目录高考链接l3.（11北京）Being a parent is not always easy

30、,and being the parent of a child with special needs often carries with _ extra stress.lA.it B.them C.one D.himl【答案】Cl【解析】本题较难，但根据句意“作一名家长并不是很容易，并且作为一名有着特殊需要的孩子家长，由于当这种特殊需要的孩子家长而带来额外的压力”。分清指代，it 指代上文being the parent of a child with special needs内容，carry的宾语为extra stress,with it 表示原因，防止误选C.，由此可知选Al【考点定

31、位】考查代词it用法。高考链接l4.（09浙江卷）_ is our belief that improvements in health care will lead to a stronger,more prosperous economy.l A.As B.That C.This D.Itl【答案】D.l【解析】本题it代替that improvements in health care will lead to a stronger,more prosperous economy，而其他选项均不可以充当形式主语。l【考点定位】考查it作形式主语。高考链接l5.If I can help_

32、,I dont like working late into the night.l A.so B.that C.it D.theml【答案】Cl【解析】此题考查it的特殊用法。it可用于某些动词之后，无确切的含义，构成习语。此处If I can help it意为“如果我有办法的话”。有时我们也可以说成It cant be helped或There is no help for it。表示“实在没有办法”。常见口语中带it 的惯用语:(youve/Ive)got it懂了,明白了;forget it算了吧,别提了,休想,不可能;Dont mention it(别人道谢时回答)不客气;Take

33、 it easy别急，慢慢来;“make it+时间”把 定在(某时);It/all depends那要看情况而定;Its hard to say情况很难说;It comes to nothing没什么结果。高考链接l6.（2019年安徽卷）Catherine bought a postcard of the place she was visiting,addressed to and then posted it at the nearby post officelAit;her Bit;herself lCherself;her Dherself;herselfl【答案】Bl【解析】考查代词。第一空不定代词it指代前面的postcard；第二空to后的宾语应为反身代词herself.高考链接l7.（2019 年天津卷）He didnt make _ clear when and where the meeting would be held.lA.this B.that C.it D.thesel【答案】Cl【解析】考查it作形式主语，it代替when and where the meeting would be held其他选项均不可以充当形式宾语。docin/sanshengshiyuandoc88/sanshenglu 更多精品资源请访问更多精品资源请访问