“it”用法总结(经典版)ppt课件

it 的用法的用法 1.it作人称代词作人称代词1.1.it的最基本用法是作人称代词，主要指刚提到的最基本用法是作人称代词，主要指刚提到 的事物，以避免重复的事物，以避免重复:Zhengzhou is a beautiful city,isnt it?1.2.也可以指动物或婴儿也可以指动物或婴儿(未知性别的婴儿或孩子未知性别的婴儿或孩子):Is this your dog？No,it isnt.1.3.也可指抽象事物也可指抽象事物:It was a great surprise to me when he did a thing like that2.非人称代词非人称代词itit有时并不指具体的东西，而泛指天气、时间、环境等，有时并不指具体的东西，而泛指天气、时间、环境等，称为非人称的称为非人称的it：2.1.指天气：指天气：It is a lovely day,isnt it?It is a bit windy.2.2.指时间指时间:It was nearly midnight when she came back.2.3.指环境指环境:It was very quiet in the caf.2.4.指距离：指距离：It is half an hours walk to the city centre.引导词引导词it1.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.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。1)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、人称一致和否定转移也要注意主谓一致、人称一致和否定转移的问题。的问题。It is they who are our friendsIt 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2.It is not until+被强调部分被强调部分+that.该句型也是强调句型。主要用于强凋时间该句型也是强调句型。主要用于强凋时间状语，译成汉语状语，译成汉语“直到才直到才”，可以说是可以说是 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 film star.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 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.)that.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 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 后的从句应该用虚拟语气，值得注意的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常用过去时态表示虚拟常译为“是（正是）的是（正是）的时侯时侯”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，that 引导的是主语从句，主引导的是主语从句，主句中的句中的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.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：important，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.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,no use,useless 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 foreign 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6123结构结构。6指主句中常用的动词：指主句中常用的动词：think,believe,make,find,consider,feel；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 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 it 指时间，指时间，主句中的时态常是一般将来时或过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去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 引导一个状语从句。常译为，引导一个状语从句。常译为，“看起来好象看起来好象”如果与事实不相符合，则用虚拟语如果与事实不相符合，则用虚拟语气。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 dying5）.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，该句型引导的从句是真正主语，该句型常译为常译为“不论（是否）没关系。不论（是否）没关系。It doesnt matter if they are old.6）make it 及时赶到及时赶到;成功成功;办成办成 You can make it if you hurry.You neednt worry;he will make it.7）put it 说说,评价评价 “He is an honest man.”Tom put it.用用It作形式主语的句型：作形式主语的句型：(1)It is adj.to do sth.It is difficult to translate this article.翻译这篇文章翻译这篇文章很难。很难。(2)It is adj.for/of sb.to do sth.It is important for us to learn English.学习英语对我学习英语对我们很重要。们很重要。Its kind of you to help me.你帮助我真是太好了。你帮助我真是太好了。(3)It is up to sb.to do sth.“应由某人负责应由某人负责”或或“是某人的职责是某人的职责”。Its up to you to decide whether to take the job or not.接不接受这份工作由你自己定。接不接受这份工作由你自己定。(4)It is adj.thatclause It is important that we should pay close attention to grain.关注粮食对我们很重要。关注粮食对我们很重要。(5)It is(no)good/use/useless doing sth.It is no use trying again It is of no use to try again.再试也没用。再试也没用。(6)It is worthwhile doing sth./to do sth.It is worthwhile spending/to spend much time on it.在这件事上花时间是值得的。在这件事上花时间是值得的。(7)It happens thatclause It happened that John was the only witness.碰巧约翰碰巧约翰是唯一的证人。是唯一的证人。(8)It occurs to/strikes sb.thatclause 某人突然想某人突然想到到 It suddenly occurred to/struck me that I hadnt seen Peter all day.我突然想到，我一整天都没看见彼得。我突然想到，我一整天都没看见彼得。(9)It is said/reported/announced/(well)knownthat It is known to us all that he means well.我们都知道他我们都知道他是好意的。是好意的。(10)It takes sb.some time to do sth.It took us one month to complete this project.我们我们花了一个月完成这项工程。花了一个月完成这项工程。It作形式宾语的句型作形式宾语的句型:(1)主语主语vt.(think/consider/feel/suppose/believe etc.)it adj to do sth.I found it difficult to explain to him what happened.我我觉得向他解释清发生了什么事很困难。觉得向他解释清发生了什么事很困难。(2)主语主语vt.it useful/useless/no good/no use doing sth.He thought it no use going over the subject again.他认他认为再讨论这个问题没有用了。为再讨论这个问题没有用了。(3)主语主语vt.itadj.thatclause He didnt make it clear when and where the meeting would be held.他没有明确说明会议在什么时间、什么地他没有明确说明会议在什么时间、什么地点举行。点举行。(5)see to it that务必使务必使，保证使，保证使 Will you see to it that the luggage is brought back?你你能保证行李会被拿回来吗？能保证行李会被拿回来吗？(6)表示喜欢，恨等心理方面的动词如表示喜欢，恨等心理方面的动词如:like,love,hate,appreciate,dislike等后加上等后加上it作形式宾语，再加上作形式宾语，再加上that/if/wh从句作真正宾语。从句作真正宾语。Id appreciate it if you would like to teach me how to use the computer.如果你愿意教我如何用电脑我将不胜如果你愿意教我如何用电脑我将不胜感激。感激。I hate it when people talk with their mouths full.8）.It的一些习惯用法的一些习惯用法uHow is it with your study?学习好吗？学习好吗？uThats it.这就对了。这就对了。uIt went hard with him.他身遇不幸。他身遇不幸。uIt is all over with me.我完蛋了。我完蛋了。uWe must fight it out.我们必须坚持到底。我们必须坚持到底。uI cant help it.我没有办法。我没有办法。