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1、Section Grammar,语法 专项突破,it的用法()1(教材P26)There is no doubt that the earth is becoming warmer(see Graph 1)and that it is human activity has caused this global warming rather than a random but natural phenomenon.,that,2(教材P26)It was a scientist called Charles Keeling,made accurate measurements of the am
2、ount of carbon dioxide in the atmosphere from 1957 to 1997.3(教材P26)They also agree that it is the burning of more and more fossil fuels has resulted in this increase in carbon dioxide.4(教材P29)It was during the 20th century the temperature of the earth went up about one degree Fahrenheit.,who,that,th
3、at,上个单元中，我们已经学习了it作代词和形式主语、形式宾语的用法，本单元将继续学习it引导强调句的用法。,.强调句的基本用法1含义强调句就是把句中要强调的部分(通常是主语、宾语、状语或状语从句)放在It is/was和that/who之间，原句中剩余部分放在that/who之后。It was him who I met in the park yesterday.我昨天在公园见到的人是他。,2强调句的一般疑问句式“Is/Was it被强调部分that/who其他剩余部分？”Was it Li Ping that/who he met yesterday?他昨天遇到的人是李平吗？,3强调句的
4、特殊疑问句式“被强调的疑问词is/was itthat其他剩余部分？”Whats it that Professor Liu teaches us this year?刘教授今年到底教我们什么？For what is it that she turned down our help?什么原因使得她拒绝我们的帮助的？When and where was it that you got to know Mary?究竟在何时何地你认识的玛丽？Who was it that came up with the bright idea?究竟是谁提出了这个好主意？,4强调句的识别如果把强调结构去掉，句子的意
5、思是完整、清楚的，句子结构也是完整的，这个句子就是强调句。如果把强调结构去掉后，意思不通顺，结构也不完整，则句子不构成强调句式。It was because he refused to obey the policeman that he was sent to the police station.他是因为拒绝服从警察而被送到警察局的。把强调结构去掉，则变为：He was sent to the police station because he refused to obey the policeman.因为他拒绝服从警察，所以被送到了警察局。去掉强调结构后，句子结构和意义仍然完整，说明这
6、是个强调句。,.强调句的特殊用法强调句与其他句型的结合，注意以下几种用法。1强调句型和名词性从句的结合句式特征为：整个强调句型用作名词性从句或者在强调句型中含有名词性从句时，从句要用陈述语序。Ive already forgotten where it was that you put the dictionary.我已经忘了你到底把字典放到哪里了。,2强调句型和定语从句的结合句式特征为：在强调句型的被强调部分或其他部分中找出一个先行词，附上修饰该部分的定语从句，这样整个句子结构就变得非常复杂。应特别注意不要混淆定语从句的关系词和强调句型中的that/who部分。It was playing
7、computer games that cost the boy plenty of time which he ought to have spent doing his lessons.是玩电脑游戏花去了这个孩子大量的应该用在功课上的时间。,3强调句型和not.until句型的结合“It is/was not until被强调部分that其他剩余部分”。It was not until he came back that I knew the result.直到他回来，我才知道结果。,.强调句应注意的问题1即使被强调成分是句中的时间状语、地点状语、原因状语等，也不能用when，where，
8、because等而要用that。It was in front of the bank that the old lady was robbed.老太太是在银行前面被抢劫的。,2在强调句型中有时考查主谓一致与比较结构，有时也考查用rather than，not.but.等连接的平行对比结构。连接平行对比结构时既要注重比较结构，又要注意主谓一致，属于较复杂的句式。It is/was not.but.that.“不是而是”(that后的谓语动词与but后的名词或代词保持一致)It is/was.not.that.“是而不是”(that后的谓语动词应与not前的名词或代词保持一致)It is/was
9、.rather than.that.“是而不是”(that后的谓语动词应与rather than前的名词或代词保持一致)Personally I think it is the sales manager，rather than the salesgirls，that is to blame.依我看，我认为是销售经理而不是女售货员们要受到责备。,3强调句型的反意疑问句句式It is/was被强调部分that.，isnt/wasnt it?It was Alice and her boyfriend who sent the old man to the hospital，wasnt it?是爱
10、丽丝和她的男朋友把这位老人送到的医院，不是吗？,4强调句型的省略形式句式特征为：在一定的上下文中，强调句型的某个部分可以省略，解题时要特别注意将其复原并加以比较。Who is making so much noise in the garden?是谁在花园里弄这么大的噪音？It is the children(who are making so much noise in the garden)是孩子们。,5易与强调句混淆的几个句型(1)It is时间when.“当的时候；时间是”when引导的是时间状语从句，主句中的it指时间，表语由具体的时间充当。试比较：It was ten oclock
11、 when we got home last night.我们昨晚到家时十点了。(状语从句)It was at ten oclock that we got home last night.我们昨晚是在十点到家的。此句是强调句，去掉“It was.that”后句子仍然完整合理，注意that不能改成when。而第一句不是强调句。,(2)It was/will be.before.“过就”It was not/will not be.before.“不久就”主句中的it指时间，表语多是long，not long，three days，two weeks等表示“一段时间”的词或短语。试比较：It w
12、as three days before he went to Beijing.三天后他就去了北京。It will not be long before he finishes his job.不久他就能完成工作。It was three days ago that he went to Beijing.他是三天前去的北京。第三句是强调句，去掉“It was.that”后句子仍然完整合理。,单句语法填空1It wasnt until in high school I began to trust other people again.2In recent years,stress has be
13、en regarded as a cause of medical problems.However,like so many other things,it is only too much stress does you harm.3It is how you handle each challenge counts.4It was in the school hall the tea party was held.5It is not who is right but what is right is of great importance.,that,that,that,that,th
14、at,6I think a pity that you didnt come to the concert last Sunday.7It was what he said at the meeting last night made me angry.8It was not until I reached there I began to know something about the matter.9It is because English is being widely used at present we learn it hard.10It is five years my elder brother joined the army.11It wont be long you regret for what youve done.12It was not until he got into trouble he realized that he shouldnt have been addicted to smoking.,it,that,that,that,since,before,that,
