外语系零八翻三216蒋丽芝.ppt

Hello, everyone! Lets begin our class!,今天，我们将学习it的多种用法，你们知道它的哪些用法呢？ It” 用法及其句型和固定搭配，是英语语法的“重点、难点，又是近几年考试的热点，因此在学习中应给予足够的重视。现将it用法归纳如下：,1.IT”用作实词,表达以下概念:指代前文提到的事物，前文中的this, that；替代前文中的内容；指代一位性别不明的小孩或未知的人；指代未指明但谈话双方都知道的那件事；指代时间、天气、气候、距离等自然现象 。 eg. （1）用作人称代词，代替前文提到过的事物。 The train has arrived. It arrived half an hour ago. （2）用以代替提示代词this, that。 Whats this? Its a knife. Whose watch is that? Its mine.,（3）起指示代词的作用，指一个人或事物。 Who is knocking at the door? Its me. 4）指环境情况等。 It was very noisy (quiet) at the very moment. （5）指时间、季节等。 What time is it? Its eight oclock. It often rains in summer here. （6）指距离。 It is a long way to the school.,It用作形式主语替代作主语的从句、动词不定式、动名词，而把真正作主语的从句、动词不定式、动名词置于句尾。,2.It用作形式主语,当代英语中，通常用it 做形式主语，将不定式和动名词置于谓语后面，特别是主语较长时，或在一些习惯用法中。 谓语是系表结构（be + 形容词 / 名词）时，常将不定式后置，构成句型 “it + be + 表语（形容词 / 名词）+ 不定式”。 例 1 It is my duty to care for that patient. 照料那位病人是我的职责。（做主语的不定式to care for that patient 后置，it 为形式主语） 例 2 It is not an easy thing to master a foreign language. 掌握一门外语不是件容易的事。,例 3 It isnt right to speak ill of someone behind his back. 在别人背后说坏话是不对的。 当谓语是 take，make，pay，cost ，require， feel，need 等动词时，或者是与情绪有关的动词 delight，amuse，excite，annoy，irritate 等时，习惯上常用 it 做形式主语，并将不定式后置。 例 1 It takes only ten minutes to get there. 到那儿只需十分钟。,例 2 It pays to be honest. 诚实是不会吃亏的。 例 3 It feels good to stay away from the crowded city. 能远离拥挤的城市，感觉真不错。 例 4 It annoyed her to see someone spit on the ground. 看见有人随地吐痰让她很生气。 4） 但表语是（of）no use，not any use，not the slightest use， no good， not much good，fun等时，常用动名词（不用不定式）做主语并后置，用 it 做形式主语。 例如 Its no use crying over spilt milk. 覆水难收。,用来替代作宾语的从句、动词不定式、动名词，而把真正作宾语的从句、动词不定式、动名词置于句尾。 It 作形式宾语的常见句型： 1. verb+ it+ adj./noun (for/of) to do/clause (verb=think, believe, suppose, consider, feel, make, keep) 、 It is/was+被强调部分+ that(who) 强调句型用来强调谓语动词以外的任何句子成分。当被强调部分是人时也可以用who。,3.It用作形式宾语,4.用在强调句中,在使用强调句型时需注意以下几点： . 1.请注意强调句型的特殊疑问句 2. 在强调原因状语从句时，只能强调由because所引导的从句。 3. 在强调not until结构时必须把not与until一起放到被强调的位置上。 4. 注意强调句型与定语从句的区别。 应用强调结构，应注意以下几点： 被强调代词的格应与原句保持一致，其谓语动词与原句保持一致。 E.g. It is I who am going to Beijing next week. 是我将于下周去北京。 It is him who I want to see. 我想见的正是他。, 强调结构也有其否定、疑问或感叹形式。特殊疑问句中只有疑问词可以被强调，构成“特殊疑问词 + be + it + that + 剩余部分”结构。 E.g. It is not only blind men who make such stupid mistakes. 并非仅仅是盲人才犯这样愚蠢的错误。 Was it during the Second World War that he died? 他是在第二次世界大战期间死的吗？ Where was it that you met Tom yesterday? 昨天你是在哪儿碰到汤姆的？,What a wonderful time it was that we had at the party! 我们在聚会上玩得是多么高兴啊！ 强调结构的反意疑问句，附加问句中的主语用it而不用句中主语。 E.g. It was at eleven last night that I knew the good news, wasnt it? 是昨天晚上十一点我知道这个好消息的，不是吗？, It is where you come from that you should return to, isnt it? 你是从哪里来的就应回哪里去，不是吗？ 对not until(till)结构中状语进行强调时，not需置于被强调 的部分之中，构成 “It is/ was not untilthat”结构 It was not until she took off her dark glasses that I recognized she was a famous film star. 直到她摘下墨镜，我才认出她是位著名影星。 It was not until he finished all his homework that he went to bed last night. 昨天晚上直到他完成作业才睡觉。 本结构不能用来强调让步状语从句，原因状语从句中只有because引导的可被强调。 E.g. It was because he was seriously ill that he didnt go to school yesterday.,是因为他病得厉害，昨天才没有上学。 如何判定含有定语从句的强调结构呢？仔细分析that或who在句中的作用，若that或who可有可无（结合it be来分析），则为强调结构，否则就是定语从句。 It was in the lab (that was set up by Mr. Smith) that they finished the experiment. 正是在史密斯先生建立的实验室里他们完成了这项实验。（lab后的that不可省略，因为它作该句的主语，句中第二个that才是强调结构的标志。）,It was Li Hong (who came from Hunan) that won the first prize in the contest. 是来自湖南的李红获得了竞赛的头奖。 强调结构和主语从句句型（指It + be + adj. /n. + that + 剩余部分）的区别： 含有主语从句的句子在译成汉语时不可加上“正是”或 “就是”之类的字眼，而强调结构可以；b. 含有主语从句的句子若删掉It be that/ who, 则原句在结构上和意义上均不成立，而强调结构若去掉结构标志却仍然成立。 E.g. It is true that he once went to Canada.,他曾经去过加拿大是真的。（不能去掉It is和that，否则原句不成立，故本句是含有主语从句的复合句。） It was on December 11,