人教版(新教材)高中英语选修3Unit2 Healthy Lifestyle优质学案：Grammar-动词不定式作主语

1、Grammar动词不定式作主语图解语法脉络动词不定式作主语动词不定式 与动名词作 主语的区别厂动名词作主语通常表示抽象动作；而不定式作主语表示具体动作(1)图解语法脉络动词不定式作主语动词不定式 与动名词作 主语的区别厂动名词作主语通常表示抽象动作；而不定式作主语表示具体动作(1)动名词作主语时,通常用以表示一件的事或经验 (2)不定式短语通常用来表示一件未完成的事或目的(1)不定式作主语，有时用入当形式主语，把作真正主语的不定式短语后置(2)常用动名词作真正的主语，it作形式主语的句型有：Its no good (use, fun) doing/lts a waste of time doi

2、ng等感知语法规律.To see is to believe.To do morning exercises is useful for our health.3.1t is interesting to play with snow in winter.4.1ts important fbr human beings to keep the balance of nature.K自主发现X.动词不定式在句中可作主语。.可以用it作形式主语,真正的主语是动词不定式。精讲语法知识不定式是非谓语动词的一种，没有人称和数的变化，在句中可以作主语(有名词 和代词的作用)，通常表示具体的、特定的行为。L

3、不定式作主语的用法不定式位于句首To study English well is not easy.学好英语不容易。To save money now seems impossible.现在好像不可能存钱。K名师提醒表示单一概念的动词不定式作主语时，谓语动词用单数。To make up for lost time is not possible.要弥补失去的时光是不可能的。(2)多数情况用it作形式主语，把真正的主语(动词不定式)置于句末，特别是不定 式短语较长时。常用于以下句式中。It+be+名词+ to doIts our duty to take good care of the old

4、.照顾老人是我们的责任。It+be+形容词+ (for/of sb)+to doIt is difficult for us to finish writing the composition in a quarter of an hour.我们很难在一刻钟内写完这篇作文。“It is stupid of you to write down everything, the teacher says.老师说：“你把每件事都写下来，真是太蠢了。”K名师提醒该句式结构中for sb前常用表示事物的特征、特点的形容词，如easy, hard, difficult, interesting, impos

5、sible 等。Its necessary for you to lock the car when you do not use it.当你不用车的时候，锁车是有必要的。(2)of sb前一般用表示人物的性格、品德及主观感情或态度的形容词，如good, kind, nice, clever, foolish, right 等。It was silly of us to believe him.我们真愚蠢，竟然相信了他。疑问词+不定式短语作主语可置于句首。How to use the computer is a question.如何使用计算机是个问题。即时训练1补全句子It takes ab

6、out ten minutes to walk to the bank.步行去银行大约用十分钟时间。It was easy for us to go to sleep_ at the_ end of the day feeling a little misunderstood.(2020江苏卷阅读 D)在一天结束的时候，我们很容易在被误解的感觉下入睡。 It，s very kind of you to say so.你这样说真是太好了。It was a special time to bond with my children and it filled them with the wonde

7、rment of books.（2020-全国卷 H 阅读 D）这是一个特殊的时刻，我和我的孩子们建立了联系，让他们沉浸在书的奇妙中。When to ho3 the jneeting hasnt been decided yet.什么时候开会还没有定下来呢。The implication of these results is that to gain the greatest health benefits from exercise, it may be wise to skip eating Erst.（2020江苏卷阅读 C） 这些结果说明，要想从运动中获得最大的益处最好先不吃东西。2

8、.动词不定式与动名词作主语的区别（1）动名词作主语通常表示抽象动作；而不定式作主语表示具体动作。Smoking is prohibited here.这里禁止抽烟。（抽象）It is not good for you to smoke so much.你抽这么多烟对你身体很不好。（具体）（2）动名词作主语时，通常用以表示一件的事或经验。不定式短语通常用来 表示一件未完成的事或目的。Climbing mountains is interesting.爬山很有趣。（经验）To finish the task will take a long time.完成这项任务将要花费很长时间。（具体）（3）不

9、定式作主语，一般用it当形式主语，把作主语的不定式短语后置。动名词作真正的主语的句型有:Its no good （use, fun） doing/Ifs a waste of time doing 等 oIt took me only five minutes to finish the job.我仅用了5分钟便完成了工作。It is no good arguing with him.He never listens to others.和他争论没用，他从不听 别人的。即时训练2单句语法填空Walking (walk)is a good form of exercise for both yo

10、ung and old.Driving (drive) a car during the rush hour is tiring.It is no use crying (cry)over the split milk.Playing (play)with fire is dangerous.To play (play)with fire will be dangerous.运用语法规那么I .单句语法填空1.Sometimes its hard to let (let)go.For many British people, that can apply to institutions and

11、 objects that represent their countrys pastage-old castles, splendid homes.and red phone boxes.(2020江苏卷阅读 B).He will find it is easy to make friends in this city.To get (get) there by bike will take us half an hour.4.It was a big deal for us to load (load)up and go to the local library, where my kid

12、s could pick out books to read or books they wanted me to read to them.(2020全国卷 II阅读D)ts very nice of you to get me two tickets for the World Cup.fs necessary for you to give up smoking.How long did it take you to finish (finish)the work?.As is known, only working (work) hard leads to happiness.He s

13、ays its not easy to convince (convince) people that nutria fur is green, but he has no doubt about it.(2020-全国卷 H 阅读 C).How to learn (learn) English well is important.n.补全句子fs kind of you to do me favour.你能帮助我真是太好了。2.Respecting the elderly is a Chinese traditional virtue and a symbol of civilization

14、 as well.尊敬老人是中华民族的传统美德，也是文明的象征。3.1fs hard to tell .exactly how many people agree with him , but research indicates that the numbers have been rising for some time.(2020全国卷HI 阅 读C)很难确切说出有多少人同意他的观点，但研究说明，这个数字一段时间以来一直 在上升。4.11 运 difficult for us to finish writing the composition in a quarter of an hou

15、r. 我们难以在十五分钟内完成这篇作文。.Nomatter howbrighta talker youare , there are timeswhen its bette】 to remain silent.(浙 江 卷)不管你多么能说会道，有些时候保持沉默会更好。.How to cope with he rising cost of living becomes a daily discussion topic.如何应对日益上涨的生活费用成为人们日常讨论的话题。in.语法填空People use the word “firiend in a 1.(various) of ways.A fr

16、iend can mean anything from an acquaintance(泛泛之交)to someone youve known.Whoever they are, friends are an important part of life at every stage.For some people, making friends is easy.For others, it can be 2.struggle.Ifs easy for people who know how to connect with others.But you dont need to be clev

17、er or 3.(charm) to make friends.People who make friends easily know how to be 4.(them).There9s an old saying： A friend is someone who knows you well-and 5.(like) you anyway.vThere are three simple things you can do to make friends.First, you have to like yourself.Make a list of your 6.(strong), tale

18、nts and achievements.That way, when you meet new people, youll know 7. you have to share.Next, learn how to listen.To succeed in friendships, you need to show an interest 8.others.Ask questions about other people.Finally, its a good idea 9.(join) a club or take a class.That way, you can meet people who have similar interests.Good friends 10.(usual) like the same things.K语篇解读U本文是说明文，主要介绍了交朋友的三个简单步骤。.variety K考查固定搭配。句意：人们用各种各样的方式使用“朋友”这个词。 根据句意可知，此处考查固