1、 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:Taian 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 that 1.it作人称代词作人称代词1.4.it 指未知的人。指未知的人。A
2、有人敲门有人敲门Theres a knock at the door.Who is it?Its the milkman.B 在电话里在电话里“Oh,by the way,there was telephone call for you?”Who was it?C 确认某人为何人确认某人为何人Her face lighted when she saw who it was.二二.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,i
3、snt 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.三三 强调句强调句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 fa
4、ther 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 you
5、r 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
6、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
7、式。It was not until she took off her dark glasses that I realized she was a famous film 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.四四 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.
8、+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 th
9、at 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）
10、，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
11、 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 fir
12、st 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6）定语从句中的形式主语）定语从句中的形式主语The man whose bu
13、siness it is to look after the children is not here.Those were the graduate assistants whose responsibility it was to do the research work in the lab.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
14、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
15、 easy，safe，common，normal，hard，difficult,dangerous，等。等。在中的形容词作表语可以用从句改写，在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，(not any good)，no use，(not
16、 any use),a waste of time等等 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 五五 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,be
17、lieve,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
18、their work in two days.六、特殊句型六、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。
19、等表示时间段的词或短语。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。常译引导一个状语从句。常译为，看起来好象如果与事实不相符合，则用虚为，看起来好象如果与事实不相符合，则用虚拟语气。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）5）.It doesnt matter whether(if).该句型中该句型中whether
20、(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.七七 模糊指代情模糊指代情况况-Do you like it here?-oh,yes.The air,the weather,the way of life.Everything is so nice.How is it going with your father?I like it in the autumn when the weather is clear and bright.I would appre
21、ciate it if you would turn down the radio.-Could you see each other at 3 oclock this afternoon?-Lets make it another time.She made it in films when she was still a teenager.We just made it in time for the meeting.Hold the ladder for methats it.The doctor advised Tony strongly he should take a holida
22、y,but it didnt help.If I can help it,I dont like working late into the night.If I come home late Ill catch it from my mother.Ill catch it due to your carelessness.As it turned out,Lee was wrong.“It”试题解析试题解析1.The Parkers bought a new house but _ will need a lot of work before they can move in.A.they B.it C.one D.which“It”试题解析试题解析1.I saw more than one clock in that shop.Will you go and buy_?A.they B.it C.which D.one
