that 在定语从句中与同位语从句中的用法
that引导从句的七种用法
that引导从句的七种用法1. That 可以用来引导宾语从句哦，就像“I think that he is very nice.”我觉得他很不错呀，这里的“that he is very nice”就是宾语从句，懂了吧？2. 嘿，that 还能引导定语从句呢！比如“She wore a dress that madeher look like a princess.”她穿了一件让她看起来像公主的裙子，这里的“that made her look like a princess”就是定语从句呀！3. 哇塞，你们知道吗，that 引导主语从句也是杠杠的呀！“That he passed the exam surprised us all.”他通过了考试这件事让我们都很吃惊呢，这里的“That he passed the exam”就是主语从句呢！4. 哎呀呀，that 引导表语从句也很牛掰呀！“The fact is that I don't like it.”事实就是我不喜欢呀，这里的“that I don't like it”就是表语从句，咋样？5. 嘿哟，可别忘了 that 能引导同位语从句哦！“The news that he won the first prize excited us.”他赢得一等奖的消息让我们很兴奋，这里的“that he won the first prize”就是同位语从句哟！6. 哼，that 还可以用在一些固定句型中呢，像“It is said that...”据说怎么样怎么样，“It is believed that...”人们相信什么的。
7. 哈哈，that 引导的从句在一些比较句中也很常见呀！“He is tall er than that I thought.”他比我想的要高呢，这里的“that I thought”就是一个从句哟！8. 哎呀，还有一些特殊的用法呢，像是在强调句中，“It is...that...”，“It is he that helped me.”就是他帮助了我呀。
THAT用法情况总结
THAT用法总结第一、that 用作形容词（后接复数名词时用those）它用来指已被提到的人或物；也可表对比，指两个中较远的那个。
What about that book you borrowed from me last month？请注意，that 有时候在句子中具有喜欢或轻蔑等感情色彩。
that little son of his 他那个小宝贝儿子That George！乔治那家伙！（含有轻蔑语气）第二、that 用作代词。
1. that 用作指示代词（复数形式是those），其指代意义同形容词用法，同时它还可以用作定语从句中的先行词；还可为了避免重复，代替前述名词。
.that用来替代前面提到的特指的事物,所代替的名词可以是可数名词,也可以是不可数名词.代替可数名词可以用the one替换.但其前面不可用任何限定词修饰.例如:1)The population of China is larger than that of Japan.(that代替不可数名词population,不可用the one替换)2)The headteacher in your class is younger and more active than that in theirs.(that代替可数名词headteacher,可用the one替换)that 代替指物的单数可数名词或抽象不可数名词，一般是特指的those 代替指人或指物的复数名词，一般是特指的=the onesone 代替指人或指物的单数可数名词，一般是泛指的ones 代替指人或指物的复数名词，一般是泛指的That is what he told me.What is that (which) you have got in your hand?The price of rice is higher than that of flour.2. that 用作关系代词，引导限制性定语从句。
that用法详解
that用法详解that用法详解想要学好考研英语怎么能不知道that的用法呢?下面就让店铺为大家详解一下吧。
that是英语中十分常见的单词，用法灵活多样，是英语中最常用的词汇之一。
正因为它是我们认为自己最熟悉的单词，反而容易忽视它。
在考研英语中，对that的考查包括三个方面：(1)that作指示代词的用法;(2)that作连词引导各类从句时，需要准确辨别从句类型。
一、that 作限定词或代词that可以作限定词或代词连接名词或名词短语，也可单独使用，用以指代人或者物。
此外，that不仅可以指代单独的人或物，还可以指代一句话。
例：Furthermore, in the early days of long line fishing, a lot of fish were lost to sharks after they had been hooked. That is no longer a problem, because there are fewer sharks around now. [2006, text3]分析：A.分析句子结构。
Furthermore, in the early days of long line fishing, a lot of fish were lost to sharks //after they had been hooked. That is no longer a problem, //because there are fewer sharks around now.第一个句子的主句为a lot of fish were lost to sharks，介词短语in the early days of long line fishing作状语，after引导时间状语从句。
第二个句子主句是That is no longer a problem, that为代词，because引导原因状语从句。
THAT的用法
that可以用来引导定语从句?主语从句?宾语从句和同位语从句,也可以在强调句中出现?不少同学对这些that从句分辨不清,以致于在平时的作业和考试中出现了一些不该出现的错误?下面笔者结合近几年的高考试题,谈谈如何运用以下四种方法来分辨that从句:一? 运用“试减法”,区别强调句型和其他从句如果把句中的it, be和that去掉,把剩余的部分作适当调整后仍然是一个结构完整?意思通顺?合乎逻辑的句子,则该句便是强调句,否则便是其他从句?例如:It was at nine yesterday that we met the film star.将It, was和that去掉后,其余部分可调整为: We met the film star at nine yesterday. 显然,句子结构完整?意思通顺,故为强调句?[考例]1. (NMET 2006) It was not until she got home___________ Jennifer realized she had lost her keys.A. whenB. thatC. whereD. before2. (2006辽宁) It was after he got what he had desired___________ he realized it was not so important.A. thatB. whenC. sinceD. asKey: 1. B2. A二? 运用“成分分析法”,区别定语从句和其他从句先仔细分析句子结构,如果that在从句中充当主语或宾语,则该从句便是定语从句?例如:We must do everything that the teacher tells us to do.that在从句中充当do的宾语,故that引导的从句为定语从句?[考例]1. (2002上海春) Is this the reason___________ at the meeting for his care-lessness in his work?A. that he explainedB. what he explainedC. how he explainedD. why he explained2. I’ll remember 2004 forever___________ is full of happiness.A. whenB. thatC. itD. whatKey: 1. A2. B三? 运用“还原法”,区别主语从句和其他从句所谓“还原”,就是去掉句首的It, 再把that从句放置句首?如果新构成的句子意思与原句相同,则该从句为主语从句,否则为其他从句?例如:It’s clear that he’s round and tall like a tree.把It去掉,再将that从句置于句首后,句子便成为: That he’s round and tall like a tree is clear. 整个句子意思与原句一样?因此, that引导的从句为主语从句?[考例](2006浙江)___________ is our belief that improvements in health care will lead to a stronger, more prosperous economy.A. AsB. ThatC. ThisD. ItKey: D?四? 运用“试加法”,区别同位语从句和其他从句同位语从句是对其前面名词的具体内容作进一步的说明和解释?若在名词和从句之间加系动词be之后,能构成一个语意通顺?合乎逻辑的新句子,则that从句便是同位语从句?例如:A story goes that Elizabeth Ⅰ of England liked nothing more than being surrounded by clever and qualified noblemen at court.在A stroy和that从句之间加上is后,句子便成为: A story is that Elizabeth I of England liked nothing more than being surrounded by clever and qualified noblemen at court. 显然, that 从句叙述的是story的具体内容,二者之间是同位关系?[考例]1. (2006四川) —It’s thirty years since we last met.—But I still remember the story, believe it or not,___________ we got lost on a rainy night.A. whichB. thatC. whatD. when2.(2006安徽) A warm thought suddenly came to me___________I might use the pocket money to buy some flowers for my mother’s birthday.A. ifB. whenC. thatD. whichKey: 1. B2. C[跟踪练习]1. Can you tell me the reason___________ he told you?A. thatB. whyC. whatD. it2. Doris’success lies in the fact___________ she is co-operative and eager to learn from others.A. whichB. thatC. whenD. why3. It is what you do rather than what you say___________ matters.A. thatB. whatC. whichD. this4. There is much chance___________ Bill will recover from his injury in time for the race.A. thatB. whichC. untilD. if5. The Foreign Ministry said, “___________our hope that the two sides will work towards peace.”A. This isB. There isC. That isD. It is6. There’s a feeling in me___________ we’ll never know whata UFO is——not ever.A. thatB. whichC. of whichD. what7. It was in the bookstore___________ I met your brother theother day.A. whereB. thatC. in whichD. whenKey: 1. A2. B3. A4. A5. D6. A7. Bthat用作连词时,本身无词义? what用作连接代词时,本身含有疑问意义?二者都可用来引导从句?但什么场合用that, 什么场合用what, 有些同学却容易弄错?一? 引导主语从句that与what都可引导主语从句? that在从句中不作句子成分,但不能省掉? what在从句中可作主语?宾语?表语或宾语补足语,也不能省掉?例如:1. What he said at the meeting was very important. 他在会上说的话非常重要? (What在主语从句中作宾语)2. What surprised us is that he did it alone. 使我们吃惊的是,他一个人做了那项工作? (What在主语从句中作主语)3. That he did it alone surprised us. 他一个人做了那项工作,这使我们吃惊? (That只是引导主语从句,在从句中不作任何成分) 也可用it作形式主语置于句首,而将that引导的主语从句移至句末?例如:It surprised us that he did it alone.二? 引导宾语从句that与what都可引导宾语从句? that在从句中不作句子成分, 一般情况下可以省掉,但若句中有两个以上的宾语从句,则只能省掉引导第一个宾语从句的that? what在从句中可作主语?宾语?表语和宾语补足语,而且不能省略?例如:1. They stopped to see what was happening. 他们停下来看看面前发生了什么事情? (what在从句中作主语)2. The teacher got angry because of what the boy had done. 因为那个男孩子所做的事,老师很生气? (what在从句中作宾语)3. The moon and the sun are just part of what we call “universe”. 太阳和月亮正是我们所说的“宇宙”的一部分? (what 在从句中作宾语)4. All the people believed (that) it was right to rescue the old temple.所有的人都认为拯救古庙是正义之举? (that在从句中不作句子成分,可以省略)5. We must believe (that) each of us is able to do something well, and that, when we discovered what this something is, we must work hard at it until we succeed. 我们必须相信我们每个人都可以把一些事情做好,而当我们领悟此事是何事之后,我们就必须努力做下去,直到成功为止?(第一个that可省略,第二个that不能省略? what引导宾语从句时, what不能省略?)三? 引导表语从句that与what都可以引导表语从句? that在从句中不作任何句子成分,但通常不能省略? what 在从句中可以作主语?宾语?表语和宾语补足语,也不能省掉?例如:1. Mary is no longer what she used to be. 玛丽不再是从前那样了? (what在表语从句中作表语)2. The question is what we should do to prevent him from going. 问题是我们怎样才能阻止他去? (what在表语从句中作宾语)3. The reason why he didn’t come today is that his mother is ill. 他今天没来的原因是他母亲病了? (that只引导表语从句,不作任何成分)四? 引导同位语从句that和what都可以引导同位语从句,对其前面名词的具体内容作详细阐述?后面常常跟同位语从句的名词有fact, idea, news, hope, belief, promise, thought, suggestion, proposal等? that在从句中不作句子成分,但不能省略? what 在从句中可以作主语?宾语?表语和宾语补足语,也不能省略?例如:1. I have no idea what we should do next. 我不知道下一步我们该做什么? (what在同位语从句中作宾语)2. He made a promise that he would study hard. 他许诺要努力学习? (that只起引导作用,在从句中不作任何句子成分)3. The boy expressed his hope that he would be a pilot when he grew up. 那个男孩子希望长大后当一名飞行员? (that只起引导作用,在从句中不作任何成分)五? 引导定语从句that可以引导定语从句,并在定语从句中作主语或宾语, that既可指人也可指物? that在从句中作宾语时可省略? what不能引导定语从句?例如:1. This is one of the buildings that were built last year. 这是去年建成的楼房之一? (that在从句中作主语,不能省略)2. The doctor (that) you met in the street yesterday came here 20 years ago. 你昨天在街上遇到的那位医生二十年前就来到了这里? (that在从句中作宾语,可以省略)学生作业本中常常会出现这样的句子:1. He did all what he could to save the patient.2. All what he needs is more time.以上两个句子都是错误的?两句中的what都应改为that? that引导的定语从句可修饰先行词all? 也可以直接去掉what? 这样一来, all和he之间是省掉了作宾语的关系代词that?that引导的定语从句和that引导的同位语从句之间的区别在于: that引导定语从句时,在定语从句中作主语或宾语(作宾语时可省略)? that引导同位语从句时,在句中不作任何句子成分,但也不能省略?六? 引导状语从句so ... that, such ... that和so that可引导状语从句? what 不能引导状语从句,但whatever; no matter what可引导让步状语从句?例如:1. He made such rapid progress in English that before long he could write articles for an American newspaper. 他在英语上取得了如此快的进步,不久就能为美国的一家报社写文章了?2. Put the little plants in the shade so that the sun won’t burn them. 请把幼苗放在阴凉处以免太阳把它们晒枯?3. Don’t believe him no matter what he may say. 无论他说什么,都不要相信他?。
that在从句中的用法
that在从句中的用法在英语中，"that"是一个常用的代词，可以在从句中作为主语、宾语、表语或同位语使用，表示特定的事物或概念。
以下是一些常见的"that"在从句中的用法：1. 主语从句：在主语从句中，"that"常被省略，但如果引导的主语太长或与主句的主语不同，通常会保留"that"。
例如：“That (that) he is a good teacher is clear.”2. 宾语从句：在宾语从句中，"that"可以省略，尤其是在某些动词（如"think"，"believe"等）后。
例如：“I believe (that) she will succeed.”3. 表语从句：在表语从句中，"that"通常不省略。
例如：“The reason why he was late was that he missed the bus.”4. 同位语从句：在同位语从句中，"that"不作任何成分，因此通常省略。
例如：“The news that he won the prize was exciting.”5. 关系代词：在定语从句中，"that"作为关系代词，可以指人或物，代替先行词在从句中充当成分。
例如：“The book that I read was very interesting.”6. 强调结构：在强调结构中，"that"用于强调某个特定的部分。
例如：“It was she that (that) found the lost child.”需要注意的是，"that"在从句中的用法可能会因为语境、习惯或避免重复而有所不同。
因此，在实际使用中，需要根据上下文和语法规则来判断是否省略"that"。
如何区分that引导的定语从句与同位语从句
(that) she told me yesterday She told me the news
她昨天告诉我的பைடு நூலகம்息是真的。
yesterday
区分技巧：
1.引导词that是否代替前面名词在从句中作成分，作成分是定语从句，不作 成分是同位语从句。
2.同位语从句和其前面的名词是同义“是”的关系，用来补充说明前面的名词。
如何区分that引导的同位语 从句与定语从句
Definition
同位语从句用来对其前面的抽象名词进行补充 说明；抽象名词与从句在逻辑上是主系表关系 （抽象名词 + be + that 从句），从句本身是一 个很完整的句子；that是连词，只起连接作用， 在从句中不作任何成分，但不能省略。
定语从句对其前面的名词加以修饰限定，从句 本身不够完整，前面的名词在从句中作成分； that是代词，代替前面的名词在从句中作主语、 宾语或表语，作宾语或表语时， that可以省略。
Summary
1. 引导词that是否代替前面名词在从句中作成分， 作成分是定语从句，不作成分是同位语从句。
2. 同位语从句和其前面的名词是同义“是”的关 系，用来补充说明前面的名词。
3. 定语从句和其前面的名词是修饰限定“的”的 关系，用来修饰限定前面的名词。
The end
Thanks for watching
2. He remembered the promise that he had made to us at the party. 定语从句
3. The fact that Chinese people are brave is wellknown. 同位语从句
4. The suggestion that he put forward at the meeting was reasonable. 定语从句
三大从句中的what,that和 which
三大从句中的what， that和 which一．在名词性从句(主语从句、宾语从句、表语从句、同位语从句)中that 不充当任何句子成分，which 作定语，What 充当主语、宾语、表语等。
Eg:It so happens that I know the man. (主语从句)We have reason to believe that the fighting on the border may develop into a full-blown war.（宾语从句）The trouble is that we are short of money.（表语从句）The fact that she looked like a sensitive , kind girl didn’t matter.（同位语从句）I don’t know which class he is in.What he does doesn’t agree which what he says.二．在定语从句中，what 不能引导定语从句，只需区分 that和which。
1.that 的先行词既可以是人，又可以是物，而which 的先行词只能是物。
2.当先行词是物时，that 和which经常可以互换。
Eg:Do you still remember the days that/which we spent together?Is this the museum that/which we visited last year?3. 不可互换的情况：用that 不用which有8种情况：(1).当先行词被不定代词修饰或先行词本身是不定代词时。
不定代词有28个：every/no/any/some (thing one body) much many (a) little/few all both none neither either each 。
that的用法总结归纳
that的用法总结归纳“that”在英文中是一个使用频率很高的单词。
它有四种词性，并且句法及语法功能纷繁复杂。
同学们如果不能熟练掌握其用法，很可能会形成英语学习的一种障碍，从而影响其学习兴趣和效率。
以下是小编为大家整理的that的用法总结，希望能帮助大家更好地认识that这个单词，提高英语水平。
第一、that 用作形容词(后接复数名词时用those)。
它用来指已被提到的人或物;也可表对比，指两个中较远的那个。
What about that book you borrowed from me last month?请注意，that 有时候在句子中具有喜欢或轻蔑等感情色彩。
that little son of his 他那个小宝贝儿子That George!乔治那家伙!(含有轻蔑语气)第二、that 用作代词。
1. that 用作指示代词(复数形式是those)，其指代意义同形容词用法，同时它还可以用作定语从句中的先行词;还可为了避免重复，代替前述名词。
That is what he told me.What is that (which) you have got in your hand?The price of rice is higher than that of flour.2. that 用作关系代词，引导限制性定语从句。
先行词可人可物，用法相当于who或which。
(但是在下列情况下多用that：先行词既有人又有物时;先行词有形容词最高级、序数词、不定代词、very，only等修饰时;先行词是不定代词时)He talked about the teachers and schools that he had visited.I think it one of the most wonderful films that the film company has ever produced.She has little information that is useful for our research.Is there anything that I can do for you?请注意，that 在定语从句中作宾语时通常可省略。
关于That的用法
关于That的用法----岳生伟我们对That一词可谓非常熟悉，同时也知道它的用法灵活多变。
这就需要我们能够全面掌握它，从而在使用的时侯能得心应手，那么本文就从高考的试题中去把握它的几种用法，方便同学们了解掌握它。
一that做指示形容词结构：that+名词或者名词短语（相当于名词的词）当名词为复数时，that改为those这种用法大家可能都很熟悉，我们来看几个例句：1，Anyone （who ever watched me play for the team back in the 1980s and early`90s`）will find that last statement hard to believe.分析：有些同学把上面划线部分误认为宾语从句，可是发现它并不是一个完整的句子。
其实这样理解是因为把that理解错了，它应该是一个指示形容词的用法。
它是后面接这个last statement名词短语，从而that last statement做find的宾语，即是find+宾语（last statement）+宾语补足语（hard to believe）。
意思就等同于此句话：that last statement is hard to believe.2,That (those) unforgettable ten days.3,Later that evening, I tearfully told Frank what I had learned that day .(07年重庆卷完型填空)二that做指示代词结构：其后不接名词，是一种指代作用。
往往是代替前面出现过的名词。
例如：4，The land of china is larger than that of America.分析：这个that就是代替前面的the land.5，That is the end of the news.分析：that就是指代说话人已经讲过的内容。
定语从句that不能省略
定语从句that不能省略定语从句that不能省略定语从句that的用法大家了解吗？以下是店铺分享的定语从句that的用法，一起来看看吧！一、定语从句that不能省略情况1.非限制性定语从句中,that有其他意思不可省2.有不定代词时3.有only时4.有序数词时5.指人又指物时6.有形容词最高级时二、定语从句中关系词的省略与不省略1.关系代词which,whom,who,that在定语从句中作宾语时可以省略.Here is the man (who/that/whom)you're been looking for.以下情况不能省略：（1）在介词+whom与介词+which中,whom,which不能省略.Do you know any shops nearby in which I can buy flowers?That is the headmaster with whom my father was talking just now.注：当介词放在动词后时,which,whom就可以省略.Who is the man (whom) you talked with just now?（2）在非限制性定语从句中,作宾语的关系代词也不能省略.Mr Green,whom you know,is the tallest in our school.The elephant is like a spear,as anybody can see.（3）在the same ...as,such...as,as...as,the same...that 中,as,that即使作宾语,也不能省略I have bought the same bicycle as you have (bought).(指同类用as)This is the same book that I read the day beforeyesterday.(that指同一个)（4）当由and,but,or等连词连接两个或两个以上的定语从句修饰一个先行词时,第一个关系代词可省,但第二,第三个不可省略.This is the book (which) I read yesterday and which I find very interesting.2.当that在从句中作补语时可以省略.He is not the man (that) he used to be.She is all (that) a teacher should be.3.在there be 结构中出现定语从句,或在定语从句中出现there be 时,用作主语的关系代词也可省略.There is a man downstairs (who) wants to see you.This is the best dictionary (that) there is in the library.4.状语的省略（1）当先行词是reason,而且定语从句中作原因状语时,关系代词可用why,that,也可以省略.The reason (why/that) he failed was his laziness.That is the reason (why) I did it.（2）当先行词是way,且在定语从句中作方式状语时,关系代词可用in which,that,也可以省略.The way (in which/that) these comrades look at problems is wrong.That was the way (in which/that) she worked the problem out.注意：当关系代词在定语从句中作主语时,不省略.例如：I don't know the way that/ which leads to the top of the mountains.(3)当先行词是time时,关系代词可用when,that 或省略.The second time (that) I saw him was in 1980.I don't know the exact time (when/that) the sports meet will take place.注意：关系代词作宾语有时也不能省略.拓展1同位语从句在复合句中用作同位语的从句叫同位语从句，常常跟在fact,idea,opinion,news,hope,belief等名词后面,用以说明该名词表示的具体内容，可以由名词、代词、短语及句子来充当同位语从句。
THAT用法总结
THAT用法总结第一、that 用作形容词(后接复数名词时用those)它用来指已被提到的人或物；也可表对比，指两个中较远的那个。
What about that book you borrowed from me last month？请注意，that 有时候在句子中具有喜欢或轻蔑等感情色彩。
that little son of his 他那个小宝贝儿子That George！乔治那家伙！（含有轻蔑语气）第二、that 用作代词。
1. that 用作指示代词(复数形式是those），其指代意义同形容词用法，同时它还可以用作定语从句中的先行词；还可为了避免重复,代替前述名词。
.that用来替代前面提到的特指的事物，所代替的名词可以是可数名词，也可以是不可数名词。
代替可数名词可以用the one替换.但其前面不可用任何限定词修饰。
例如:1)The population of China is larger than that of Japan.（that代替不可数名词population,不可用the one替换）2)The headteacher in your class is younger and more active than that in theirs。
（that 代替可数名词headteacher,可用the one替换）that 代替指物的单数可数名词或抽象不可数名词，一般是特指的those 代替指人或指物的复数名词,一般是特指的=the onesone 代替指人或指物的单数可数名词，一般是泛指的ones 代替指人或指物的复数名词，一般是泛指的That is what he told me。
What is that （which) you have got in your hand？The price of rice is higher than that of flour.2。
英语中that的用法
英语中that的用法“that”在英文中是一个使用频率很高的单词。
它有四种词性，并且句法及语法功能纷繁复杂。
同学们如果不能熟练掌握其用法，很可能会形成英语学习的一种障碍，从而影响其学习兴趣和效率。
现将that的用法总结归纳如下：第一、that 用作形容词（后接复数名词时用those）。
它用来指已被提到的人或物；也可表对比，指两个中较远的那个。
What about that book you borrowed from me last month？请注意，that 有时候在句子中具有喜欢或轻蔑等感情色彩。
that little son of his 他那个小宝贝儿子That George！乔治那家伙！（含有轻蔑语气）第二、that 用作代词。
1. that 用作指示代词（复数形式是those），其指代意义同形容词用法，同时它还可以用作定语从句中的先行词；还可为了避免重复，代替前述名词。
That is what he told me.What is that (which) you have got in your hand?The price of rice is higher than that of flour.2. that 用作关系代词，引导限制性定语从句。
先行词可人可物，用法相当于who或which。
（但是在下列情况下多用that：先行词既有人又有物时；先行词有形容词最高级、序数词、不定代词、very，only等修饰时；先行词是不定代词时）He talked about the teachers and schools that he had visited.I think it one of the most wonderful films that the film company has ever produced. She has little information that is useful for our research.Is there anything that I can do for you?请注意，that 在定语从句中作宾语时通常可省略。
中考英语--that引导定语从句,同位语从句和强调句之比较
中考英语--that引导定语从句，同位语从句和强调句之比较that这个词，用法极其广泛，除了是指示代词，也是各种各样从句的连词。
这里，我们来对比其在定语从句，同位语从句和强调句中的作用。
这也是很多英语学习者容易闹不清的点。
一. 定语从句我们首先要知道，定语从句中的连词，或者说关系词，典型的作用就是代替前面所修饰的名词或者代词（即先行词）在后面的定语从句中作成分。
这个成分可以是名词性成分，比如：主语，宾语等。
也可以是副词性成分，比如各种时间状语，地点状语，原因状语等等。
that在定语从句中，属于关系代词，所以是代替所修饰的先行词在定语从句中作名词性成分，常见的就是主语和宾语：例如：The girl that danced yesterday is my sister. 昨天跳舞的女孩是我妹妹。
（此处，that代替the girl在后面的定语从句中作主语，是发出danced这个动作的主语）The boy that you spoke to is my brother. 和你说话的那个男孩是我兄弟。
（此处，that代替the boy在后面的定语从句中作宾语，是动词短语spoke to的宾语。
二. 同位语从句要理解什么是同位语从句，我们需要先理解什么是同位语。
同位语：放在同一个位置，可以画等号的两个事物或者群体互为同位关系，通常后面的叫前面的同位语。
例如：I accept your suggestion to build a bridge here.2. I accept your suggestion that a bridge should be built here. 我接受你的建议——在此处搭建一座桥。
此处，句子1中to build a bridge here=suggestion，所以to build a bridge here和suggestion互为同位关系。
通常后面的to build a bridge here是前面suggestiond的同位语。
引导词that在同位语从句中不作句子成分
一、that在同位语从句中不作句子成分The fact that the Chinese people invented the compass is known to all．中国人发明指南针这个事实是众所周知的。
（同位语从句）The fact that he succeeded in the experiment pleased everybody．他实验成功这个事实使我们大家很高兴。
（that只起连接作用）Here comes the news that some tourists from America will come to our village．消息传来，说一些美国旅游者要来我们村。
（that只起连接作用）He has an idea that he can make the scientific instrument in a better way．他想到能用更好的方法制造这种科学仪器。
（从句是idea的具体内容）He expressed the hope that he would come to China a-gain．他表达了他要再来中国的希望。
（从句是hope的具体内容）The question when we will start the work is not decided．我们何时开始工作的问题尚未决定You have no idea how worried I was．你不知道我是多么担心。
二、that在定语从句中必作句子成分The fact that we talked about is very important．我们谈论的这个事实很重要。
（定语从句）The fact that（which）we talked about is very important．我们所谈论的那个事实很重要。
（that在从句中作about的宾语）The news that you heard is true．你听到的消息是真的。
定语从句和同位语
定语从句和同位语定语从句和同位语导语：定语从句是从句对其先行词的修饰或限制，属于形容词性从句的范畴；以下店铺为大家介绍定语从句和同位语文章，欢迎大家阅读参考!定语从句和同位语1. 从词类上区别同位语从句前面的名词只能是idea，fact，news，hope，belief，suggestion，proposal，word，thought，doubt，truth， possibility， promise， order等有一定内涵的名词，而定语从句的先行词可以是名词、代词，主句的一部分或是整个主句，如：The possibility that the majority of the labor force will work at home is often discussed.人们经常讨论大多数劳动力将会在家里工作的可能性，考研语法：定语从句与同位语从句的区别。
（同位语从句）Our team has won the game， which made us very happy. 我们的队赢了，这让我们很高兴。
（定语从句）2. 从性质上区别定语从句是从句对其先行词的修饰或限制，属于形容词性从句的范畴；而同位语从句是从句对前面抽象名词的进一步的说明和解释，属于名词性从句的'范畴，如：The news that our team has won the game was true. 我们队赢了那场比赛的消息是真的。
（同位语从句，补充说明news到底是一个消息。
）The news that he told me yesterday was true. 昨天他告诉我的那个消息是真的。
（定语从句，news在从句中作told的宾语。
）3. 从引导词及其在句子中的成分上区别有些引导词如how，whether，what可以引导同位语从句，但不能引导定语从句，如：That question whether we need it has not been considered. 我们是否需要它这个问题还没有考虑。
定语从句中that和what
定语从句中that和whatthat可以引导定语从句.what只能用来引导名词性从句，一起来看看定语从句中that和what的用法。
一.在引导名词性从句时，从属连词that一般要注意三个不(three nos)：1.不省略(no ellipsis)当从属连词that引导主语从句、表语从句和同位语从句时，that不省略。
Eg. 1) That he was able to come made us happy. (That 引导主语从句不可省略)2)The truth is that I didn’t go there. (that引导表语从句不可省略)3)The news that our team has won is true. (that引导同位语从句不可省略)但在非正式文体中that 引导宾语从句时可以省略，除下列两种情况外：that在宾语从句中不能省略的情况.(1). 在主+谓+it(形式宾语)+宾补+that，从句(真正宾语) 的句型中不省略Eg: 4) He made it quite clear that he preferred to study English.(that不可以省略)他很明确地说他宁愿学习英语。
(2). 由连词and连接的两个由that引导的宾语从句中, 则第二个宾语从句前的that不省略。
Eg: 5) He told me that he would come and that he would come on time.(第一个That可以省略，但第二个that不可以省略。
)他告诉我他将来而且他将准时来。
2.不作成分(no component)that 在名词性从句中不作任何句子成分。
Eg. 6)Sydney kept his promise that he would always do anything he could for Lucie to make sure of her happiness.(that在句中引导同位语从句，但在句中不作任何成分)7))That you don’t like him is none of my business. (that在句中引导主语从句，但在句中不作任何成分，也不省略)3. 没词义(no meaning)that 在名词性从句中没有汉语意思。
that的用法归纳总结
that的用法归纳总结篇一：that在从句中的用法小结that在从句中的用法小结that除了用作指代代词以外，还可以用作连词引导名词性从句、状语从句，用作关系代词，引导定语从句。
其用法如下：一、that用作连词，引导名词性从句。
1. 引导宾语从句，that无实际意义，可省略。
例如：We must remember (that) the enemy will not perish of himself.我们必须记住敌人是不会自行消灭的。
Kitty said (that) she would call again after supper.凯蒂说她晚饭后再来但是，当一个句子很复杂，句中有多个并列的宾语从句时，特别是第一个宾语从句特别长的情况下，后面宾语从句前的that不可省略。
例如：I wish (that) we could go sightseeing in Hangzhou this summer and that we could buy some books in Shanghai on our way back.我希望今年夏天到杭州去玩玩，并在返回的路上到上海买点书。
2. 用于主语从句中，that一般不能省略。
例如：That we need more equipment is quite obvious.我们需要更多的设备，这是很明显的。
That she is still alive is a consolation.她还活着，这是使人感到宽慰的。
（以上两句中的that不能省）有时主语从句较长，这时往往用it作形式主语，而把that从句移后。
例如：It is good you are so considerate.你这么周到是很好的It is certain that they will all eventually turn to socialism.可以肯定他们最后都必将转到社会主义方面来。
微视角透析that在同位语从句和定语从句中的角色
【摘要】名词性从句和定语从句是高中英语学习和教学中的重中之重，它们和状语从句一起构成可谓是英语教学中的三座大山，而that 穿梭于名词性从句和定语从句之间，让很多学习者感到迷惑。
本文就that 在两大从句中的特点，给学习者做出诠释和分析，从细微处击破学习中的拦路虎。
【关键词】that 同位语从句定语从句微视角透析that 在同位语从句和定语从句中的角色广西贺州市贺州高级中学王玉梅首先，我们要从概念上弄清楚什么是名词性从句和定语从句。
从词性上讲，名词性从句相当于名词，在句子中起到名词的作用，名词可以在句子中充当宾语、表语、主语、同位语，因此名词性从句包括宾语从句、表语从句、主语从句、同位语从句。
定语从句从词性上讲是相当于形容词，因此定语从句也叫做形容词性从句。
形容词是用来修饰名词和代词的，因此修饰名词和代词的句子就称为定语从句。
本文将重点选取同位语从句和定语从句进行对比分析that 的角色，因为同位语从句和定语从句在外在呈现形式上存在很大相似之处。
1.同位语从句和定语从句概念的区别1.1同位语从句在主从复合句中，在句中作某一名词尤其是抽象名词的同位语，一般位于该名词之后，解释说明该名词的具体内容的从句。
同位语从句前面的抽象名词一般有：fact,news,idea,truth,hope,problem,information,wish,promise,answer,evidence,report,explanation,suggestion,conclusion 等。
例如：The suggestion that students should learn some -thing practical is worth considering.学生应该学些实用的东西的建议值得考虑。
同位语从句是对抽象名词suggestion 的内容进行了解释，其内容即是学生们该学习些有用的东西。
1.2定语从句在主从复合句中，对名词和代词起修饰限制的作用，被定语从句所修饰的名词和代词叫先行词，引导定语从句的词成为关系代词或者关系副词。