1、高中英语语法解析-名词性从句在句子中起名词作用的句子叫名词性从句(Noun Clauses）。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。 一 主语从句主语从句是在复合句中充当主语的从句，通常放在主句谓语动词之前或由形式主语it代替，而本身放在句子末尾。引导主语从句的连词有：that, whether, who, whom, what, whatever, whose1.常规主语从句，既复合句在句中充当一个主语，那么这个句子就是主语从句(1)That he
2、 finished writing the composition in such a short time surprised us all.(2)Whether we will go for an outing tomorrow remains unknown.(3)Who will be our monitor hasnt been decided yet.(4)Whom we must study for is a question of great importance.(5)What caused the accident remains is unknown.(6)What we
3、 need is time.(7)Whose watch was lost is unknown.(8)Whatever you did is right.注：连词位于句首不能省略2. It 作形式主语和it引导强调句的比较（为了防止句子头重脚轻，通常把形式主语it放在主语位置，真正主语搁置于句末）It 作形式主语代替主语从句，主要是为了平衡句子结构，主语从句的连接词没有变化。而it引导的强调句则是对句子某一部分进行强调，无论强调的是什么成分，都可用连词that。被强调部分指人时也可用who/whom。例如： a) It is a pity that you didnt go to see t
4、he film. 你不去看那场电影真可惜。 b) It doesnt interest me whether you succeed or not.我对你成功与否不感兴趣。 c) It is in the morning that the murder took place.谋杀案是在早上发生的。（强调句型） d) It is John that broke the window.是John打碎的窗户。（强调句型）3. 用it 作形式主语的结构(1) It is 名词 从句 It is a fact that 事实是 It is an honor that 非常荣幸 It is common
5、knowledge that 是常识(2) It is 形容词 从句 It is natural that 很自然 It is strange that 奇怪的是(3) It is 不及物动词 从句 It seems that 似乎 It happened that 碰巧 It appears that 似乎(4) It 过去分词 从句 It is reported that 据报道 It has been proved that 已证实 It is said that 据说3. 主语从句不可位于句首的五种情况：（1）if 引导的主语从句不可居于复合句句首。（2）It is said /rep
6、orted结构中的主语从句不可提前。例如： 正确表达：It is said that President Jiang will visit our school next week. 错误表达：That President Jiang will visit our school next week is said. （3）It happens/occurs结构中的主语从句不可提前。例如： 正确表达：It occurred to him that he failed in the examination. 错误表达：That he failed in the examination occurr
7、ed to him.（4）It doesnt matter how/whether 结构中的主语从句不可提前。例如： 正确表达：It doesnt matter whether he is wrong or not. 错误表达：Whether he is wrong or not doesnt matter.（5）含主语从句的复合句是疑问句时，主语从句不可提前。例如： 正确表达：Is it likely that it will rain in the evening? 错误表达：Is that will rain in the evening likely?4. what 与that 在引导
8、主语从句时的区别 what 引导主语从句时在句时在从句中充当句子成分，如主语宾语表语，而that 则不然。例如： a) What you said yesterday is right. b) That she is still alive is a consolation 二宾语从句宾语从句就是在复合句中作宾语的名词性从句，通常放在主句谓语动词 (及物动词) 或介词之后。(1) 由that引导的宾语从句(that 通常可以省略), 例如： I heard that he joined the army. 我听说他参军了。注： that在引导宾语从句时也并不是任何情况下都可以省略。在以下情况下
9、，that不能省略:that从句位于句首时，that不可省略:That he ever said such a thing I simply dont believe. 我简直不相信他曾说过这样的话。that宾语从句的状语部分位于从句前部时。I promised that if anyone could set me free,I would make him king over the earth.我曾许诺如果有人把我放了，我就让他成为全世界的国王。当主句的状语部分位于that宾语从句前时。Abraham Lincoln later said himself that he only wen
10、t to school a little now and a little then.亚伯拉罕林肯自己后来说他只不过是时断时续地接受教育。that引导的宾语从句作介词宾语时，that不能省略:I know nothing about him except that he is from the south.对他我一无所知，只知道他是南方人。主句的谓语动词与宾语从句之间有插入语时。When he got to England,he found,however,that his English was too limited.然而当他到英国时，他发现他的英语很有限。当一个谓语动词带两个或两个以上的
11、that引导的宾语从句时。(只有第一个可省略）Then he said （that） French was the most beautiful tongue in the world,and that we must keep it among us and never forget it.他说，法语是世界上最美的语言，我们必须坚持说法语，永远也不要忘记它。宾语从句是双宾语中的直接宾语时。I must never tell anyone that I could not see the cloth.我决不能告诉任何人我看不到那布。宾语从句的主语是this/that，或用this/that修饰
12、主语时。He said that that was a good idea.他说那是个好主意。在直接引语中，主句和宾语从句被隔开时。“I;m sorry to tell you,”he said,“that you didn;t watch carefully enough what I did.”我很遗憾的告诉大家，你们没有仔细观察我所做的一切。宾语从句的主语是非谓语动词或主语从句时。The old lady then explained that what she was looking for was a pair of gloves for a girl.那位老太太解释说她在为一个女孩
13、找一双手套。(2)从属连词if/whether。连词whether可引导主语从句、宾语从句和表语从句，不可省。if引导宾语从句。宾语从句是肯定句时，whether,if可互换；但whether常和or not连用，if一般不与or not连用,宾语从句是否定句时，一般用if引导。如:I don;t know if/whether I should tell you.不知我是否应告诉你。I wonder whether it is true or not.不知这是不是真的。I don;t care if it doesn;t rain.天下不下雨我不会在乎。用if引导宾语从句如果会引起歧义，应避
14、免使用if而用wheter。试比较：Please let me know if you want to go.Please let me know whether you want to go.if从句可理解为宾语从句，意为“请告诉我你是否想去”；此句又可理解为条件状语从句意为“如果你想去的话，请告诉我一声”。作介词宾语时，只能用whether,不能用if。(介词常可省略）如：Everything depends （on） whether we have enough experience.一切都取决于我们是否有足够的经验。(3)连接代词who, whom, whose, what, whic
15、h, whoever, whatever, whichever连接副词 where, when, how, why。如:Who or what he was, Martin never learned.他是什么人？他是干什么的？马丁根本不知道。I wonder what hes writing to me about. 我不知道他要给我写信说什么事。Ill tell you why I asked you to come. 我会告诉你我为什么要你来。You may do what you will. 你可做任何你想做的事。有关宾语从句的其它一些要点.宾语从句的语序必须是陈述语序。如：Do yo
16、u know why winter is colder than summer?你知道为什么冬季比夏季冷吗?.如宾语从句有自己的宾语补足语，则用it作形式宾语，而把宾语从句后置。其句型为：“主语+谓语+it+补足语+宾语从句”。如： We think it important that we should master at least one foreign language.我们认为掌握至少一门外语是重要的。注意：(1)连词that引导的名词性从句很少作介词的宾语，只用在except,but和in等少数几个介词后。其它一些介词的宾语从句如由连词that引导，则需用it先行一步，作形式宾语。
17、如： He is a good student except that he is careless.他是个好学生，只不过有点粗心。See to it that children don;t catch cold.当心孩子别感冒了。 (2)that引导表语从句时，在句中无词义，只起连接作用，但不可省去。His idea is that we should go there at once.他主张我们立即去那儿。.宾语从句的否定转移。在think, consider, believe, suppose, expect, fancy, guess, imagine等动词后的宾语从句，有时谓语尽管是
18、否定意思，却不用否定形式，而将think等动词变为否定形式。如：I dont think you are right. 我认为你错了。I dont believe they have finished their work yet. 我相信他们还未完成他们的工作。I dont suppose he cares, does he? 我想他不在意，是吗？.某些形容词或过去分词后常接宾语从句，这类形容词或过去分词有sure, glad, certain, pleased, happy, afraid, surprised, satisfied等，连词that可省略。That 引导的从句还常跟在下列形
19、容词后作宾语：Anxious, aware, confident, convinced, determined, proud, worried, sorry, thankful, ashamed, disappointed, annoyed, pleased, hurt, satisfied, content 等。也可以将此类词后的that 从句的看作原因状语从句。如：I am not sure what I ought to do.我不能确定我该做什么。Im afraid you dont understand what I said.恐怕你没领会我说的意思。Im surprised tha
20、t I didnt see all that before.我好奇怪，我以前没看到过。Mother was very pleased her daughter had passed the exams.妈妈为她的女儿通过了考试而感到高兴。.有关that的忌讳：后边不能直接跟that 从句的动词这类动词有Allow, refuse, let, like, cause, force, admire, condemn, celebrate, dislike, love, help, take, forgive等。这类词后可以用不定式或动名词作宾语，但不可以用that引导的宾语从句。例如：I admi
21、re their winning the match. (right)I admire that they won the match. (wrong)不可用that从句作直接宾语的动词有些动词不可用于“动词间接宾语that从句“结构中，常见的有Envy, order, accuse, refuse, impress, forgive, blame, denounce, advise, congratulate等。例如：He impressed the manager as an honest man. (right)He impressed the manager that he was a
22、n honest man. (wrong)介词宾语从句.宾语从句也可用作介词的宾语。有时介词可以省略。如：He was deeply displeased by what had occurred that day.他对那天发生的事感到很不快。I walked over to where she sat. 我走向她坐的地方。I am curious as to what he will say. 我很想知道他要说什么。Your success will largely depend upon what you do and how you do it.你是否成功将主要取决于你做什么和怎样做。I
23、 dont care (for) who marries him. 我不管谁跟他结婚。Be careful (as to) how you do that. 你要注意做这件事的方式。.作介词的宾语：连词that引导的名词性从句很少作介词的宾语，只用在except, but, in,besides后。其他一些介词的宾语从句如果由连词that引导，则需用it先行一步，作形式宾语。如：He is a good student except that he is careless.（that一般不省）他是一个好学生，只是有点粗心。You may rely on it that I shall help
24、 you. 你可以指望我会帮助你的。介词宾语不可以用which来引导，而要用what来引导。如：Are you sorry for what youve done?你为你所做的一切感到内疚吗？介词宾语只能用whether,不能用if。(介词常可省略）Everything depends （on） whether we have enough experience.一切都取决于我们是否有足够的经验。补充:if、whether在名词性从句中的使用介词的宾语从句，不定式作宾语，都可用whether引导。whether也可引导主语从句，表语从句，同位语从句，还可引导让步状语从句，这时却不能换成if。引
25、导条件从句时，只能用if，而不能用 whether。 不用if，用whether的情况：在标语从句和同位语从句中。例如： The question is whether the film is worth seeing. The news whether our team has won the match is unknown.在主语从句中，只有用it作形式主语时，whether和if都能引导主语从句，否则，也只能用 whether。例如： whether we shall attend the meeting hasn,t been decided yet. It hasn,t been
26、decided whether(if) we shall attend the meeting .后面直接跟动词不定式。例如： He doesn，t know whether to stay or not . 还有关联词只能用whether 或if，不能用 that的情况如下： 若doubt一词作“怀疑”解接宾语从句时，主语为肯定句用wether或if，主句为否定句或疑问句用that。例如： I doubt whether he will come soon. I do not doubt that he will come soon. Do you doubt that he will co
27、me soon？ 注意：下面这个例句中doubt的含义为“认为 .不必可能”。I doubt that he will come.（我认为他不可能来）注：whatever可以引导名词性从句，同时起先行词和关系代词的作用。相当于anything that或all that，有任何一切这类意思。此时不能用no matter what替换。.三、表语从句表语从句就是用一个句子作为表语。说明主语是什么或者怎么样，由名词、形容词或相当于名词或形容词的词或短语充当，和连系动词一起构成谓语系动词有：be, keep, remain, stay, seem, appear, look, feel, smell
28、, sound, taste, become, grow, turn, get, go,等。构成：主语+ 连系动词+表语从句（一个句子作表语）表语从句定义：在一个复合句中，充当表语的是一个句子，那么这个句子就叫做表语从句。连接表语从句的连接词有：连词： that（不作成分，没有词义；不能省略）whether （不作成分）连接代词：what, who, , which, whoever，whomever，whichever ，whatever等关系副词：when, where，why, howHe has become a teacher. 他已经成为一名教师。 He has become wh
29、at he wanted to be ten years ago. 他已经成为了他10年前想成为的。 His suggestion is good. 他的建议是好的。 His suggestion is that we should stay calm. 他的建议是，我们应该保持冷静。 注意事项A表语从句一定要用陈述语序。 The question is when can he arrive at the hotel. 错The question is when he can arrive at the hotel. 对B不可以用if，而用whether 连接表语从句(as if 例外）。 引
30、导宾语从句时可以互换if/whether， 位于介词后要用whether，位于句首时要用whether.引导主语从句时,whether引导的从句可以放在主句前和后，而if从句只能放在主句后。引导表语从句， 同位语从句时要用whetherThe question is if the enemy is marching towards us. 错The question is whether the enemy is marching towards us. 对It looked as if he had understood this question. 对C不像宾语从句，在有表语从句的复合句中
31、，主句时态和从句时态可以不一致。 The question is who will travel with me to Beijing tomorrow. 对The question is why he cried yesterday. 对Dthat在表语从句中具有三个特点：不作成分；不能省略；没有意义。E表语从句只能置于主句之后，而主句的动词只能是连系动词。 例如： The problem is how we can get the things we need.问题是我们怎样能弄到我们需要的东西。The scissors are not what I need. 这把剪刀不是我所需要的。W
32、hat I told him was that I would find him a good play. 我告诉他的是我会给他找个好剧本。That is what I want to tell you.那就是我想要对你讲的。(what在表语从句中充当直接宾语) That is why she failed to pass the exam. 那就是她考试不及格的原因。(why 在表语从句中充当原因状语) F“That is why.”是常用句型， 意为“这就是的原因/因此”， 其中why引导的名词性从句在句中作表语， 该句型通常用于针对前面已经说明过的原因进行总结，如： That is wh
33、y you see this old woman before you know, Jeanne. 珍妮， 这就是现在这个老太婆出现在你面前的原因。(前文提到Jeanne对老妇人显得苍老憔悴深感诧异， 说话人对她讲述了其中的原因之后，用这一句来进行概括)。G. “That is why.” “That is the reason why.” “That is because.”辨析： (1)“That is why.”与“That is the reason why.”同义， 从语法结构上讲， “That is the reason why.”中why引导的是个定语从句， 将其中的the re
34、ason去掉则与“That is why.”结构一样， 例如： That is (the reason) why I cannot agree. 这就是我不能同意的理由。 (2)“That is because.”句型中从属连词because引导的名词性从句在此作表语， 这也是个常用句型， 意为“这就是为什么/因为”。“That is because.”与“That is why.”之间的不同在于：“That is because.”指原因或理由， “That is why.”则指由于各种原因所造成的后果， 例如： He did not see the film last night. Tha
35、t is because he had to help his little sister with her homework.昨天晚上他没有去看电影， 那是因为他得帮助他的妹妹做作业。(第一句话说明结果， 第二句话说明原因) He had seen the film before. That is why he did not see it last night.他以前曾看过那部电影， 因此他昨天晚上没有去看。(第一句话说明原因， 第二句话说明结果) H. 当主句的主语为reason,或者是由why引导的从句时,与它们相关的表语从句用that,而不能由because引导; because 引
36、导表语从句时只能用于It/That/This is /was because_句型中. 1.The reason why I was late was that I missed the train.2. I was late. It/That/This was because I missed the train.I. 名词（主语）+系动词+表语从句主语名词常常是表示事实，真理的名词，如：fact, truth 表示看法，观点、问题、麻烦的名词，如：idea, opinion, belief, view, news, advice, feeling, suggestion, plan, tr
37、ouble, question, problem, 1.The fact is that our team has won the game.2.The truth is that she was the very person we are looking for.必须记住：1. that引导表语从句时不能省.2. if不能引导表语从句.3.除that外的所有引导词都有自己的意义。4. 除that, whether外的所有引导词都须在从句中充当相应的成分 5. what在表语从句中译成“ 东西；事情; 内容” 案例分析 考题1The traditional view is _ we slee
38、p because our brain is “programmed” to make us do so. (2007上海) A. when B. why C. whether D. that 答案 D 解析 下划线处之后是包含一个原因状语从句的表语从句， 如果看不出它是充当整个句子结构的表语从句将难以把握整个句子的意思。因此， 应选择可引导名词性从句且不充当任何成分的that。 考题2 You are saying that everyone should be equal, and this is _ I disagree. (2004) A. why B. where C. what D
39、. how 答案 B 解析 下划线处的引导词引导系动词is后的表语从句并在该表语从句中充当地点状语(“disagree”属于不及物动词， “I disagree”本身是完整的主谓结构)， 下划线应填入引导词where， 表语从句“where I disagree”的意思是“我不同意之处、 我不同意的地方”。 考题3 I drove to Zhuhai for the air show last week. Is that _ you had a few days off? (1999) A. why B. when C. what D. where 答案 A 解析 下划线处的引导词引导与系动词
40、is连用的表语从句并在该表语从句中充当原因状语， 下划线应填入表示“因此”(指因某种原因所造成的结果)的引导词why。 _ she couldnt understand was _ fewer and fewer students showed interest in her lessons. (2000上海) A. What; why B. That; what C. What; because D. Why; that 答案 A 解析 第一个下划线处的引导词引导主语从句并在该主语从句中充当宾语， 特指她所不理解的事情， 应填入关系代词型的引导词what； 第二个下划线处表示“因此”(指因某
41、种原因所造成的后果， 由why引导对应的名词性从句)而不是“为什么”(指原因、 理由， 由because引导对应的名词性从句)， 应填入引导词why。 _ made the school proud was _ more than 90% of the students had been admitted to key universities. (2003上海春) A. What; because B. What; that C. That; what D. That; because 答案 B 解析 第一个下划线处的引导词引导主语从句并在该主语从句中充当主语， 特指令校方骄傲的事情， 应选
42、用关系代词型的引导词what； 第二个下划线处引导表语从句表示原因、 理由， 应由that引导对应的名词性从句。 Are you still thinking about yesterdays game? Oh, thats _. (2003北京春) A. what makes me feel excited B. whatever I feel excited about C. how I feel about it D. when I feel excited 答案 A 解析 A选项的意思是“令我感觉激动的事物”； B选项的意思是“我觉得激动的任何事物”； C选项的意思是“我对它感觉的方式
43、”； D选项的意思是“令我感觉激动的时间”。四个选项中A最适合跟代表“game”的主语that对应， 充当表语从句。 表语从句与宾语从句的关系宾语从句和表语从句都属于名词性从句。其作用跟名词在句中的作用相同。故充当宾语的句子叫宾语从句，充当表语的句子叫表语从句。四. 同位语从句同位语从句就是在复合句中作名词的同位语的名词性从句。1. 同位语从句的功能 1.同位语从句对于名词进一步解释，说明名词的具体内容，一般由that引导，例如： 1) The kings decision that the prisoner would be set free surprised all the people
44、.2) The order that all the soldiers should stay still is given by the general.2.whether eg：The question whether we should call in a specialist was answered by the family doctor3.连接代词what, who, whom, whose, which 1).I have no idea what size shoes she wears 2).I have no idea which wine is bestits a ma
45、tter of personal taste. 3).The question who will take his place is still not clear.2. 同位语在句子中的位置 同位语从句有时可以不紧跟在它所说明的名词后面，而是被别的词隔开。例如： He got the news from Mary that the sports meeting was put off.3. 同位语从句与定语从句的区别(1) 定语从句中的that既代替先行词，同时以在从句中作某个成分（主语或宾语），而同位语从句中的that是连词，只起连接主句与从句的作用，不充当句中任何成分。(2) 定语从句是
