[备战高考英语]名词性从句的用法.doc

名词性从句的用法名词性从句包括主语从句表语从句宾语从句和同位语从句引导名词性从句的连词有:who；whom；whose；what；which；when；where；why；how；that；if；whether；whatever；whenever；wherever；however 等 名词性从句注意事项:从句的语序为陈述句；连词that不充当任何成分；what总是要充当主语表语宾语等 if和whether的区别:if引导宾语从句和条件状语从句；whether引导主语从句表语从句宾语从句和同位语从句 (一)主语从句 用作主语的从句，叫主语从句主语从句可以直接放在句首；也可用it作形式主语，而将从句放在句末 常见的用it作形式主语的复合结构: It is + 名词 + that从句；It is a fact(a pity，a shame，no wonder，good news.)that. It is + 形容词 + that从句；It is necessary(strange，important，wonderful，possible，likely，.)that. 这类句中谓语动词多为(should) + 动词原形 It is + 过去分词 + that 从句；It is said(reported，decided，believed，.)that. It + 不及物动词 + that 从句；It seems(happened，doesnt matter，has turned out，.)that. What you need is more practice. 你需要的是更多的练习(what在从句中作need的宾语) What is hard is to do good all ones life and never do anything bad. 难的是人的一生都做好事从不做坏事(what在从句中作主语) What he will be in the future is known to us. 我们知道他未来会干什么(what在从句中作be的表语) Who will go makes no difference. 谁去都一样 How this happened is not clear. 这件事是怎样发生的还不清楚 Why he did that wasnt quite clear. 他为什么那样做相当不清楚 Whether she will join us wont make too much difference. 她是否加入我们没多大区别(此处不能用if) Whoever comes will be welcome. 不管谁来都受欢迎(whoever在名词性从句中相当于anyone who) Whatever she did was right. 不管她做什么都是正确的(whatever在名词性从句中相当于anything that) It is possible that I may not be able to come. 可能我不能来了(it是形式主语，真正的主语是that I may not.部分) It doesnt seem likely that she will be here. 看来她不会来这了 Isnt it strange that he should have left without telling us?他没有告诉我们就离开了，难道不奇怪吗? It occurred to me that he had forgotten to take his notebook with him. 我想起来，他忘记随身带笔记本了 That we need more equipment is quite obvious. 很明显，我们需要更多的设备 Has it been announced when the planes are to take off?已经宣布飞机什么时候起飞了吗? (二)表语从句 用作表语的从句叫表语从句它位于连系动词(如be，seem，remain 等后) The question is whether we should accept their invitation. 问题是我们是否应当接受他们的邀请 The city is no longer what it used to be. 这个城市不再是曾经的样子 This is why we put off the meeting.(why表结果)这就是为什么我们推迟了会议 That is because he was ill.(because表原因)那是因为他生病了 The reason for his absence was that he was ill.(此处不能用because代替that . 句型:The reason. is that.)他缺席的原因是他生病了 as if 引导的表语从句有时可用虚拟语气，表示可能性小 He acted as if he hadnt eaten for a long time. 表示建议命令要求一类的表语从句要用虚拟语气: My suggestion is that you should practise reading English every day. (三)宾语从句 作宾语的从句叫宾语从句 作动词的宾语: He doesnt know where the post office is. 他不知道邮局在哪里 在动词suggest，order，demand，require等表示建议命令要求的宾语从句要用虚拟语气(宾语从句的谓语用should + 动词原形，should 可省略) I suggested that you(should)start right now. 我建议你马上开始 如果宾语从句后有宾语补足语，要用形式宾语it，而将从句放到补足语后面 I thought it strange that he didnt pass the exam. 我觉得他没通过考试很奇怪 在think，believe，suppose，expect等动词后的宾语从句中，如果从句谓语是否定含义，则不用否定形式，而将主句谓语动词think等变为否定形式 I dont think you are right. 我想你是不对的 He doesnt know where the post office is. 他不知道邮局在哪里 在think，believe，imagine，suppose，guess，hope等动词以及Im afraid等后，可用so代替一个肯定的宾语从句，还可用not代替一个否定的宾语从句: Do you believe it will clear up?你认为天会放晴吗? I believe so.(I dont believe so. /I believe not.)我认为会(我认为不会) (2)作介词的宾语: Did she say anything about how we should do the work?他有没有说我们应当怎样做这个工作? That引导的宾语从句只有在except，in，but，besides等少数介词后偶尔可能用到 Your article is good except that it is too long. 除了太长外，你的论文很好 有时在介词和其宾语从句的中间加形式宾语it Ill see to it that everything is ready. 我将负责把一切准备好 (3)作形容词的宾语: Im afraid that I have made a mistake. if和whether引导宾语从句的区别，即用whether不用if的情况有: 作介词宾语，用于whether + to dowhether or not和用作discuss的宾语等 It depends on whether it is fine. 要看天气是否晴朗 Im not sure whether to leave this afternoon. 我不敢肯定今天下午是不是要出发 He can not decide whether or not to take the exam. 他不能决定参不参加考试 We are discussing whether we will hold a meeting this weekend. 我们在讨论这个周末是否要举行一场会议 doubt用于肯定句中，宾语从句可以用if或whether引导 I doubt if(whether)you will come for a visit tomorrow. 我怀疑你明天是否要来拜访一下 doubt用于否定句或疑问句中，宾语从句用that引导 He doesnt doubt that his mother will give him a ride home for sure. 他很确信他的妈妈会开车带他回家 (四)同位语从句 同位语从句跟在一个名词后(如fact，idea，news，hope，belief，thought，doubt，proof，belief等)，对其作进一步解释 I have no idea that you were here. 我不知道你在这里 He cant answer the question how he got the money. 他不能回答他是如何拿到那笔钱的 同位语从句和定语从句的区别: 从意义上讲，前者对名词加以解释说明，后者对名词进行修饰限定从结构上讲，前者由连接词引导，后者由关系词引导从内涵上讲，前者所说明的名词与从句没有逻辑关系，that不可省略后者所限定的名词是从句逻辑