15it引导的结构.pptVIP

IT用法 It 用法及其句型和固定搭配是重点、难点，又是近几年的热点，因此应给予充分的重视，现将it用法归纳如下：一、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……  1. it的用法 (1). it用作人称代词 ① it用作人称代词，通常指人以外的生物和事物，无阴阳之分。如：There is a car near the building. It is my neighbour’s. 楼旁有辆小汽车，它是我邻居的。Mr Zhang wrote a novel. It is about the miserable life of a young woman. 张先生写了一部小说，它是关于一个年轻妇女悲惨生活的。 ② it有时可用来代替小孩 (child) 和婴儿 (baby) 。 如：The child smiled when it saw its mother. 小孩看到母亲就笑了。 (2).it可用作指示代词相当于this和thatIt is a very good translation.这是一篇很好的译文。 (3).代表前面已提到的或将要发生的某件事情I had a talk with our boss. It was very helpful.我同我的上司谈了一次话，这次谈话很有帮助。(it代表前句的内容)They were asked to complete the task in two weeks. It is not an easy job. 要求他们两周内完成任务，这可不是件容易的事。(it代表前句的内容) (4).指时间、距离和自然现象等，此时it在句中作主语What time is it now? It’s half past eight.几点了？ 八点半。(指时间)Is it very far to the station? 到火车站很远吗？(指距离) It 作形式主语的常见句型： 1. 代作主语的动词不定式，其句型为 (1) It be adj. (for sb.) to do sth. 此处adj. 通常为描述事件的形容词：easy, difficult, hard, necessary, unnecessary, possible, impossible, likely, unlikely, right, wrong, important, unimportant, legal, illegal, well-mannered, ill-mannered, polite, impolite, clear, obvious, certain, suitable, proper, fit, useful, useless, dangerous… 例 It is illegal (for a teenager) to drive a car without a license.  (2) It be adj. of sb. to do sth. 此处adj. 通常为描述人的形容词：kind, unkind, nice, rude, cruel, considerate, thoughtful, thoughtless, careful, careless, silly, foolish, stupid, clever, wise, crazy. 例 Its kind of you to help me with the problem. (3) It替代作主语的动名词的常见句型 Its no good/use doing… Its (well)worth doing… Its (well)worth ones while doing/to do… Its (well)worth while doing/ to do 例 Its no use crying over spilt milk 2. It替代作主语的从句常见句型  (1) It is + noun +从句 例 It is no secret that the president wants to have a second term at office. (2) It is adj. +clause Its surprising that… (should)………竟然…… Its a pity/shame that…(should)………竟然…… 例 Its important that you