主语从句讲解与练习.docVIP

主语从句一、概述：在句子中起名词作用的各种从句统称为名词性从句。根据它们在句中的语法作用，这类从句又可分为主语从句、同位语从句、表语从句和宾语从句。?二.主语从句主要有三类：（1） 由连词that引导的主语从句:引导词that无含义,在句中不做成分,不可以省。例如：That you will win the medal seems unlikely.你想获得奖牌看起来是不可能的。That you are so indifferent bothers me.你如此冷淡使我很烦恼。That she survived the accident is a miracle.她在事故中幸免于难简直是奇迹。（2） 用连词 whether 引导的主语从句:whether有含义(是否),在句中不做成分,不可以省。 例如：Whether she is coming or not doesn’t matter too much.她来不来都无关紧要。（3） 用连接代词引导的主语从句(在由连接代词who, whose, whom, which, what, whoever, whomever, whichever, whatever引导的名词性从句中，其连接代词在句中起名词性作用，担当一定成分).例如：What you need is more practice.你所需要的是更多的训练。What I want to know is this. 我想知道的就是这事。Whatever we do is to serve the people.我们无论做什么都是为人民服务。 （4）用连接副词when, where, why, how引导的名词性从句(其连接副词有含义,在句中作状语。) eg:Where we should leave it is a problem. When they will come hasn’t been made pubic.他们什么时候来还不知道。 三.注意点: 1.it 做形式主语,而将主语从句放在句末（尤其是当谓语较短时）。例如：That light travels in straight lines is known to all.光沿直线传播，这是众所周知的事。=It is known to all that light travels in straight lines.众所周知光沿直线传播。When the plane is to take off has not been announced .飞机何时起飞还没有宣布。= It has not been announced when the plane is to take off.还没有宣布飞机何时起飞。(当what引导的主语从句表示“…的东西”时，一般不用it作形式主语。)错:It is a book what he wants.对:What he wants is a book. 他想要的是本书。例如：Has it been settled who will be sent to carry out the task ?谁将被派去执行这项任务决定了吗 ？ 固定用法和译法（1） It is +名词+从句It is a fact that… 事实是……It is good news that … ……是好消息It is a question that … ……是个问题It is common knowledge that … ……是常识类似的名词还有：a pity；a wonder；a good thing； no wonder； surprise等。例如：It is a mystery to me how it all happened.这一切是怎么发生的是个谜。It is common knowledge that the whale is not a fish.鲸鱼不是鱼，这是常识。It is no surprise that Bob should have won the game.鲍勃会赢得这场比赛，这不足为奇。（2） It is +形容词+从句It is necessary that … 有必要……It is clear that … 很清楚……It is likely that … 很可能……It is important that … 重要的是……类似的形容词还有：strange; natural; obvious; true; good; wonderful; possible; unlikely; quite; unusual; certain; e