1、英语选修7（人教版）第四学时 Grammar一、关系代词关系代词who，whom，whose，which，that等代替先行词，指人或物，并在从句中充当主语、宾语、定语等成分。关系代词在定语从句中作主语时，从句谓语动词的人称和数要和先行词保持一致。1who，whom 代替的先行词是指人的名词或代词，that代替的先行词可以是人，也可以是物。Is he the man who/that wants to see you？(who/that在从句中作主语)语 法 精 讲He is the man whom/that I saw yesterday.(whom/that在从句中作宾语，可以省略)2w
2、hose 用来指人或物(只用作定语，若指物，它还可以与of which互换)。They rushed over to help the man whose car had broken down.Please pass me the book whose cover is green.Please pass me the book the_cover_of_which is green.语 法 精 讲3which所代替的先行词是指事物的名词或代词，在从句中可作主语、宾语等。A prosperity which/that had never been seen before appears in
3、 the countryside.(which/that在从句中作主语)The package which/that they are carrying is too heavy.(which/that在从句中作宾语)语 法 精 讲二、关系代词that 的用法1不用that的情况。(1)在引导非限制性定语从句时，不能用that，只能用which。The tree，which is four hundred years old，is very famous here.(2)介词后不能用that，只能用which。We depend on the land from_which we get ou
4、r food.语 法 精 讲2只能用that的情况。(1)在there be 句型中，只用that，不用which。There is a room in the building that is still free.(2)不定代词，如anything，nothing，the one，all，much，few，any，little等作先行词时，只用that，不用which。Finally，the thief handed everything that he had stolen to the police.语 法 精 讲(3)先行词有the only，the very修饰时，只用that。T
5、his is the only book that is worth reading.(4)先行词有序数词、形容词最高级修饰时，只用that。We will never forget the first lesson that our English teacher gave us.(5)先行词既有人，又有物时只用that。He told me the places and persons that he visited in London.语 法 精 讲三、关系副词关系副词when，where，why代替的先行词是时间、地点或原因的名词，在从句中作状语。1关系副词when，where，why
6、的含义相当于“介词which”结构。Beijing is the place where/in_which I was born.Is this the reason why/for_which he refused our offer?语 法 精 讲2关系副词在定语从句中只能作状语。如果先行词是表示时间、地点、原因的名词，关系词在定语从句中充当主语或宾语，关系词就不能用when，where，why，而要用which，that；作主语时that/which不省略，作宾语时可省略。I will never forget the days which/thatwe spent together.(
7、that/which作宾语，可省略)This is the factory that/which(作主语，不能省略)is famous for its products.语 法 精 讲对比：语 法 精 讲习惯上总把表地点或时间的名词与关系副词 where，when联系在一起，此二题错在关系词的误用上。要准确判断先行词在定语从句中的成分(主、谓、宾、定、状)，才能正确运用关系词。语 法 精 讲四、“介词关系词”的用法1介词后面的关系词为whom，which，先行词指人时，用whom，先行词指物时，用which。先行词指原因时，用forwhich结构。2介词的选择应从两个方面考虑：(1)从句中的谓
8、语动词与先行词的搭配关系，即固定结构搭配考虑。(2)从整个句子意思方面进行确定。语 法 精 讲This is the house in_which I lived two years ago.Do you remember the day on_which you joined our club?He is the person from whom you can learn a lot.语 法 精 讲五、限制性和非限制性定语从句的区别1限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开。T
9、his is the house which we bought last month.(限制性)The house，which we bought last month，is very nice.(非限制性)语 法 精 讲2当先行词是专有名词或被物主代词、指示代词等所修饰时，其后的定语从句通常是非限制性的。Charles Smith，who was my former teacher，retired last year.My house，which I bought last year，has got a lovely garden.This novel，which I have read
10、three times，is very touching.语 法 精 讲3非限制性定语从句还能修饰整个主句。He seems not to have grasped what I meant，which greatly upsets me.Liquid water changes into vapor，which is called evaporation.注意：关系代词that和关系副词why不能引导非限制性定语从句。语 法 精 讲六、as，which 引导的非限制性定语从句在as，which 引导的非限制性定语从句中，as和which可代指整个主句，相当于and this或and that
11、。as引导的定语从句一般放在句首，也可位于主句后；which引导的定语从句一般在主句后。as有“正如”之意，which则没有这层意思。As we know，smoking is harmful to ones health.Smoking is harmful to ones health，as we know.The sun heats the earth，which is very important to us.语 法 精 讲 语 法 精 讲七、as的用法1as引导限制性定语从句时，常用于the same.as(和一样)；such.as(像样的)等固定结构中。I have got into the same trouble as he(has)2as可引导非限制性从句，常带有“正如”之意。(1)As we know，Taiwan belongs to China.(作know的宾语)(2)As is known，Taiwan belongs to China.(作从句的主语)
