名词性从句 (2).doc

名词性从句名词性从句包括主语从句、宾语从句、表语从句和同位语从句。主语从句：主语从句在复合句中作主语，可以放在主句谓语动词之前，也可以由it作形式主语，而将主语从句放在主句之后。如：Why he left wasnt important.It was uncertain whether he would come or not.宾语从句：宾语从句在句中作及物动词或介词的宾语。如：I felt that he had a strong will.He will talk to us about what he saw in the school.表语从句：表语从句在句中作表语，位于主句中系动词之后。如：The question is who is responsible for what has happened.He looked as if he was going to cry.同位语从句：同位语从句一般跟在某些表示抽象意义的名词后面，用来说明名词所表示的具体内容。如：I had the impression that he chose his words with care.I have no idea when he will be back.关于名词性从句我们应该掌握以下几点：一、 掌握引导名词性从句各类连接词的用法。高考试题在考查名词性从句时,常考查引导名词性从句的连接词。引导名词性从句的连接词有三大类：1. 单纯连接词：that，whether，if。它们只起引导从句的作用，并不在从句中充当任何成分。that在句中没有一定的含义。whether和if有含义，表示“是否”之意。注意，if只能用来引导宾语从句，不可引导主语从句、表语从句和同位语从句。如：He told me that he would leave office soon.She asked me whether (if) I could lend her my dictionary.2. 连接代词what, who, which, whose, whom。它们除了引导名词性从句外，还在从句中充当一定的成分。如：What can be done has been done. what引导主语从句，并在从句中作主语。Can you tell me which box is yours? which引导宾语从句，并在从句中作定语，修饰box。3. 连接副词how, why, where, when。它们除引导从句外，还在从句中作状语。如：I dont know how I can finish my work so soon.Your coat is still where you put it.二、 注意名词性从句的语序和时态。名词性从句的语序应该是陈述语序，不能用疑问语序。名词性从句的语序在历年来的高考试题中也是一个测试热点。如：Can you tell me where he lives?（where he lives是陈述语序）此外，在宾语从句中，还应注意从句的谓语动词和主句中的谓语动词在时态方面的搭配。如：I didnt know what he was doing those days.三、 注意that的用法及省略。that连接名词性从句时，只起引导从句的作用，不在从句中充当任何成分。that在引导宾语从句时常常省略，但有两个以上的宾语从句时，第一个连词that 可以省略， 第二个(包括第二个)以后的that就不可省略了。如：I know (that) she was born in the country and that she came here to look for a job.that在引导主语从句、表语从句和同位语从句时，不可省。四、 注意what和that的用法不同。what引导名词性从句时，在从句中充当一定的成分，如主语、宾语或表语等。what不可在从句中省略。而that在句中只起引导名词性从句的作用，不在句中作任何成分。试比较：1. I dont know what they are talking about. 本句中，what在句中引导宾语从句，并在从句中作talking about的宾语。2. I know (that) he is leaving for Shanghai. 本句中，that引导宾语从句，但在从句中，它不充当任何成分。 五、注意掌握whether和if的用法。whether和if都可用来引导宾语从句(但是在正式文体中，从句中有or not时，只能用whether而不用if)。但在引导主语从句、表语从句和同位语从句时，只能用whether，不能用if。六、掌握whatever与whoever的用法。whatever和whoever的用法有相似之处。它们都可用于：1 引导让步状语从句，意为“无论”。如：Whatever you do, you must do it well.Whoever you are，you must obey the rules.2 它们同时作主句和从句的一个成分，相当于“先行词+关系代词”, 即whatever相当于anything that；而whoever则相当于anyone that / who。七、引导名词性从句的连词、引导状语从句的连词和引导定语从句的关系代词或副词形式上都相同，但所起的作用不同。不要将这三类从句混为一谈。下面以where为例进行说明。如：1. He went back to the small town where he grew up as a child. 本句中的where是关系副词,引导一个定语从句，从句的先行词是town。2. Put the book where it was. 本句中的where引导的从句在整个句子中作状语, where引导一个状语从句。3. Where we shall have the meeting is not known yet. 本句的where引导一个主语从句.八、关于宾语从句的否定前移。当主句是I / We think(或suppose, expect, believe, imagine, guess等)时，其后的宾语从句如果是否定的，常把否定词not移到主句中。如：I dont think they will win the game.