while“it”用法总结.ppt

The use of “while”,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. 趁热打铁。(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,5. While there is life there is hope. 只要生命存在，就有希望。 (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 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,The use of “It”,知识要点 It的用法,（一）作人称代词 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cake） Although we cannot see it, there is air all around us. （it代替后面的air） They say he has left town, but I dont believe it. （it代替前面Theytown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 big tree. It was fully twenty metres high. （it代替前面的tree） The baby cried because it was hungry. （it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 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 South China is mild(温和的); I like it very much. （it指the climate of South China） The climate of South China is much better than that of Japan. （that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 the factory. It is eighteen square metres in area. What does it matter?,返回目录,(三)引导词it引导强调句式 1. It is + 被强调部分 + that .,使用该句型有以下几点请注意： 强调句的谓语is或was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that连接，不得使用where、when等连词. It was in the street that I met your father yesterday,被强调部分为人时，可用who(主格或宾格)和whom(宾格)代替that，用that也行。 It was your father that/whom /who I met in the street yesterday 2) It was I that/who met your father in the street yesterday 强调句中 也要注意主谓一致、人称一致和否定转移的问题。 It is they who are our friends 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when,2. It is not until + 被强调部分 + that . 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，可以说是 not . until . 的强调形式。 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.,3. it 用作形式主语 3.1 代替主语从句 1）It is + adj. +that从句 It is clear ( obvious， true， possible certain) that . “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（should + 动词原形），should 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 It is said (reported， learned) that . 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，that 后的从句要用虚拟语气（should + 动词原形），should 可以省；常译为“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（should + 动词原形），should可省去表示出乎意料，常译为“竟然”。没有这种意义时，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that 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）的时侯 It is time that children went to bed. It is the first ( second . ) time that . “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it是形式主语，that 引导的是主语从句，主句中的happen ， seem等词是不及物动词。 It happened ( so happened ) that he met his teacher in the street. 碰巧. It seems that he will be back in a few days. 看来,3.2.作形式主语替代不定式 1). It takes sb. . to do sth. 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。 常见的有： bad ， brave ， careless， clever ， cruel ， foolish ，stupid ， wise wrong等。 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： important， necessary， natural easy ， safe ，common ，normal ，hard ， difficult ,dangerous ， 等。 在中的形容词作表语可以用从句改写， 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 . 做是一份荣幸 It was is such a privilege to meet President 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. We think it important to learn a foreign language. 该句型中的it 作形式宾语，为了记忆方便我们可称该句型为“7123结构“。 7指主句中常用的动词：think,believe,make,find,consider,feel,suppose； 1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； 3指的是真正宾语的三种形式：不定式短语，动名词短语或that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 1). It is since .。 It is ( has been ) 5 years since his father died. 2). It is . when .。 “当的时候，是” It was 5 oclock when he came here.,3). It be . before . 该句型主句中的 it 指时间， 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long， not long ， 3 days ， 2 weeks 等表示时间段的词或短语，常译为“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it无意义， as if 引导表语从句。常译为，“看起来好象”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） It looks as if he were ill. （没有生病） It seemed as if he were dying.,5）. It doesnt matter whether ( if ) . 该句型中whether(if) 引导的从句是真正主语，该句型常译为 不论（是否）没关系。 It doesnt matter if they are old.,6）Id appreciate it 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.,9）make it 及时赶到;成功;办成 You can make it if you hurry. You neednt worry; he will make it. 10）catch it 被责骂; 受处罚 If I come home late Ill catch it from my mother. Youll catch it because of your carelessness. 11）. It的一些习惯用法 How is it with your study? 学习好吗？ Thats it . 这就对了。 It went hard with him. 他身遇不幸。 It is all over with me. 我完蛋了。 We must fight it out.我们必须坚持到底。 I cant help it. 我没有办法。,1.（09四川）I like this house with a beautiful garden in front, but I dont have enough money to buy _. A. one B. it C. this D. that 【答案】B。 【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。 【考点定位】it/that/one用法区别,高考链接,高考链接,2. （09浙江）Ive read another book this week. Well, maybe _ is not how much you read but what you read that counts. A. this B. that C. there D. it 【答案】 D 【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。 【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,3.（11北京）Being a parent is not always easy, and being the parent of a child with special needs often carries with _ extra stress. A. it B. them C. one D. him 【答案】C 【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A 【考点定位】考查代词it用法。,高考链接,4.（09浙江卷） _ is our belief that improvements in health care will lead to a stronger, more prosperous economy. A. As B. That C. This D. It 【答案】D. 【解析】本题it代替that improvements in health care