英语语法名词性从句分析

名词性从句

在句子中起名词作用的句子叫名词性从句（NounClauses）。名

词性从句的功能相当于名词词组，它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，

名词性从句又可分别称为主语从句、宾语从句、表语从句和同位语

从句。

引导名词性从句的连接词可分为三类：

连接词：that,whether,if（不充当从句的任何成分）

连接代词：what,whatever,who,whoever,whom,whose,which

连接副词：when,where,how,why

不可省略的连词：

1.介词后的.连词

2.引导主语从句和同位语从句的连词不可省略

Thatshewaschosenmadeusveryhappy.

Weheardthenewsthatourteamhadwon.

【比较】whether与if均为“是否”的意思。但在下列情况下，whether不能被if取代：

1.whether引导主语从句并在句首

2.引导表语从句

3.whether从句作介词宾语

4.从句后有"ornot"，例：Whetherhewillcomeornotisnotclear.

大部分连接词引导的主语从句都可以置于句末，用it充当形式主语：

Itisnotimportantwhowillgo.

Itisstillunknownwhichteamwillwinthematch.

名词性从句的十大考点全攻略

whatever,whoever,whichever引导名词性从句

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