1、Grammar What part does the underlined part serve as in each sentence?A tree has fallen across the road.You are a student.To find your way can be a problem.Smoking is bad for you.“How do you do?”is a greeting.What she said is not yet known.That we shall be late is certain.It is certain that we shall
2、be late.主语从句主语从句（Noun Clauses as the Subject）定义：定义：用作主语的从句叫主语从句，它是名用作主语的从句叫主语从句，它是名词性从句之一。引导主语从句的连接词有：词性从句之一。引导主语从句的连接词有：连词连词that,whether；连接代词连接代词who,what和和which；连接副词连接副词when,where,how和和why。1.连接词：连接词：1）从属连词：）从属连词：that，whether等等.that 引导主语从句只起引导作用，本身引导主语从句只起引导作用，本身无实际意义，在主语从句中不充当任何无实际意义，在主语从句中不充当任何成分，
3、但不能省略。成分，但不能省略。That she left him cut him to the heart.That he will come is certain.2)连接代词连接代词who，what，which,whatever,whichever,whoever What seems easy to some people seems difficult to others.Which side will win is not clear.由由whether及其他连词引导的主语从句及其他连词引导的主语从句放在句首，句后都可。放在句首，句后都可。Whether it will please
4、 them is not easy to say.3)连接副词连接副词when，where，how，why等。等。Why he did it remains a mystery.When they will start is not known yet.How he became a great scientist is known to us all.2.位置：位置：主语从句可以前置，也可以主语从句可以前置，也可以后置。用后置。用it做形式主语，而把主语从做形式主语，而把主语从句，在句末，常用下面几种句型。句，在句末，常用下面几种句型。1）It+be+表语表语 +主语从句主语从句表语：（名词
5、，表语：（名词，形容词，过去分词）形容词，过去分词）It is an honor that I was invited to attend the meeting.注意注意:1）主语从句在句首时，必须由连）主语从句在句首时，必须由连接词引导，不能省略这些连接词；接词引导，不能省略这些连接词；但是如果用但是如果用it做形式主语，而把主做形式主语，而把主语从句放在句末时，从属连词语从句放在句末时，从属连词that可以省略。可以省略。误：误：They should like each other is natural.正：正：That they should like each other is n
6、atural.正：正：It is natural that they should like each other.2)如果主语从句放在句首，不如果主语从句放在句首，不能用能用if引导，但是如果用引导，但是如果用it 做做形式主语，而把主语从句放形式主语，而把主语从句放在句末时，也可以用在句末时，也可以用if引导引导.误：误：If Mary really heard him is really doubtful.正：正：It was doubtful if Mary really heard him.3.用于用于It is important/natural/necessary/impossi
7、ble that.句型中句型中,主语从句应使用虚拟语气主语从句应使用虚拟语气,谓谓语动词用语动词用“should+动词原动词原形形”的形式的形式,should有时可有时可以省略。以省略。It is necessary that the problem(should)be discussed at once.立刻讨论这个问题很有必要。立刻讨论这个问题很有必要。4.在在It+be+suggested/advised/ordered/requested/insisted/required 中中,that从句从句的谓语也应该用的谓语也应该用“should+动动词原形词原形”的形式的形式,should有
8、时可有时可以省略。以省略。It is suggested that more modern science and technology _ textbooks.A.added to B.be added to C.is added to D.are added to(1)主语从句中用陈述语序主语从句中用陈述语序What she is afraid of is their taking her to Paris.(What is she afraid of Wrong)(2)主语从句后谓语动词用第三人称单主语从句后谓语动词用第三人称单数数That they havent phoned is s
9、trange.It 作形式主语代替主语从句，主要是作形式主语代替主语从句，主要是为了平衡句子结构，主语从句的连接词为了平衡句子结构，主语从句的连接词没有变化。而没有变化。而it引导的强调句则是对句引导的强调句则是对句子某一部分进行强调，无论强调的是什子某一部分进行强调，无论强调的是什么成分，都可用连词么成分，都可用连词that。被强调部分。被强调部分指人是也可用指人是也可用who/whom。例如：。例如：It is a pity that you didnt go to see the film.It doesnt interest me whether you succeed or not.
10、It is in the morning that the murder took place.It is John that broke the window.what 与与that 在引导主语从句时的区别在引导主语从句时的区别what 引导主语从句时在句时在从句中充引导主语从句时在句时在从句中充当句子成分，如主语宾语表语，而当句子成分，如主语宾语表语，而that 则不然。例如：则不然。例如：1)What you said yesterday is right.2)That she is still alive is a consolation.What在此引导主语从句,又做said的宾语T
11、hat 只起连接作用,不做成分1.Where shall we spend the holiday isnt decided.2.You have made a mistake is a fact.3.That is certain that we can win.4.No matter who leaves the room last ought to turn off the lights.5.It is important that a student learns a foreign language.we shallThat you haveIt isWhoevershould le
12、arn改错练习改错练习 1._ you dont like him is none of my business.2._ he said at the meeting astonished everybody present3._ the 2000 Olympic Games will be held in Beijing is not known yet.4._ well go camping tomorrow depends on the weather.5._ leaves the room last ought to turn off the lights.ThatWhatWhethe
13、rWhetherWhoever 6._ is a fact that English is being accepted as an international language.7.It worried her a bit _ her hair was turning grey.8.The Foreign Minister said,“_ is our hope that the two sides will work towards peace.”9.After Yang Liwei succeeded in circling the earth,_ our astronauts desi
14、re to do is walk in space.ItthatItwhat1 _Fashion differs from country to country may reflect the cultural differences from one aspect.(00上海）上海）A What B.That C.This D.Which2.It is pretty well understood _ controls the flow of carbon dioxide in and out the atmosphere today.A.that B.when C.what D.how 3
15、._ we will go camping tomorrow depends on the weather.A.If B.Whether C.That D.Where4._ that they can pass the written exam this time.A.That is hoped B.It is hoped C.It hopes D.That hopes 5._ leaves the room last ought to turn off the lights.A.Anyone B.The person C.Whoever D.Who 6._ is a fact that En
16、glish is being accepted as an international language.A.There B.This C.That D.ItCD 7._ in the newspaper that the price of food will go up.A.It says B.It is said C.It has said D.He is said8.It worried her a bit _her hair was turning grey.A.while B.that C.if D.forBB 9.There is no doubt _.A.that Mr.Hans
17、en is in good health B.whether is Mr.Hansen healthy C.if Mr.Hansens health was returning D.whether Mr.Hansen in healthA 10.The Foreign Minister said,“_ our hope that the two sides will work towards peace.”A.This is B.There is C.That is D.It is D 11.It is necessary that a college student _ at least a foreign language.A.masters B.should master C.mastered D.will masterB12._ made the school proud was_ more than 90 of the students had been admitted to key universities.A.What;because B.What;thatC.That;what D.That;because
