Unit 4 Breaking boundaries Using language课件-高中英语外研版选择性必修第二册.pptx

UNIT 4Breaking boundariesUsing languageit 作形式主语观察例句1It is difficult for a foreigner to learn Chinese.2Its kind of you to help me.3It is no use talking to him about it.4It is a mystery to me how it all happened.5It is believed that the flood there is the biggest in 100 years.归纳用法it作形式主语时没有具体的意义，只是帮助把真正的主语移到句子后面去，使句子显得平衡。it作形式主语时，真正的主语通常是不定式短语、ing短语或主语从句。一、一、不定式短不定式短语语作真正的主作真正的主语语，常用于下列句型中：，常用于下列句型中：It be 形容形容词词 (for/of sb.)to do sth.It be 名名词词 to do sth.It takes sb.some time to do sth.干干花了某人花了某人时间时间Its up to sb.to do sth.干干是某人的是某人的职责职责或或义务义务It is everyones duty to obey the law.遵守法律是每个人的义务。It took them a year to build the bridge.建这座桥花了他们一年的时间。It is bad manners to stare at people.盯着人看是不礼貌的。It is up to us to help those in need.帮助那些有困难的人是我们的责任。名师点津在在“Itbe形容形容词词for/of sb.to do sth.”句型中，如果形容句型中，如果形容词词描述的是描述的是sb.，则应则应用介用介词词of；如果描述的是；如果描述的是to do sth.就就用用for。Its necessary for us to use a shortwave radio to pick up the programmes.我们用一台短波收音机收听这些节目是必要的。It was foolish of him to give up the job.他放弃那工作是愚蠢的。即学即练1用所给词的适当形式填空It is not up to you _(tell)me how to do my job.It is not right _(use)these places as rubbish dumps.It was nice of them _(invite)us.to tellto useto invite二、ing短语作真正主语的情况远不及不定式短语那么普遍，常限于no good,no use,useless,waste等词的后面。It is no good/use having a car if you cant drive.有车如果不会开是没有用处的。It is a waste of time watching TV.看电视是浪费时间的。It is no use asking him.问他没有用。即学即练2用所给词的适当形式填空Its no good _(take)over the experience of foreign countries uncritically.Its no use _(cry)over spilt milk.It is worth _(make)an appointment before you go.takingcryingmaking三、用三、用it作形式主作形式主语语，主主语语从句从句作真正主作真正主语语的常的常见见句型有：句型有：1It is a pity/a shame/a fact/an honour/good news/no wonder/a wonder.that.It was a pity that the engineer couldnt come.可惜工程师没能来。2It is 形容形容词词(如：如：strange/natural/surprising/obvious/true/fortunate/wonderful/funny/possible/impossible/likely/unlikely/clear/unusual/certain/important.)that.It is certain that he will win.他一定会取胜。3It seems/happened/turned out/suddenly struck me/occurred to me.that.It happened that I wasnt there that day.恰好那天我不在那里。4It be 过过去分去分词词(如：如：said/reported/announced/decided/expected/hoped/known/believed.)that.It is reported that more than twenty people were killed in that bus accident.据报道在那次的公共汽车事故中有二十多人丧生。【温馨提示】It is suggested/required/desired/ordered/proposed.that sb.(should)doIt is necessary/important/strange/natural/essential/urgent/right.that sb.(should)doIt is requested that he give a performance at the party.有人请求他在聚会上表演一个节目。It is ordered that the radio be sent there at once.据命令,这台收音机要立刻送到那里去。即学即练3用适当的代词填空It is known _ he is one of the best teachers in our school.It suddenly occurred to me _ I knew how to solve that problem.It is strange _ he should have left without telling us.thatthatthat单句语法填空1It is very kind of you _(give)me a hand in time.2It is still a mystery _ caused the accident.3It is necessary that one _(master)the skills of operating computer.4It is known to all _ the gun powder was first invented by the Chinese.5It seemed certain _he will win the prize.to givewhatmasterthatthat