小米一籮筐
一、 定語從句是形容詞從句，其作用相當(dāng)于一個形容詞，是用來修飾前面的名詞或代詞的；同位語從句是名詞從句，其作用相當(dāng)于一個名詞，是對前面的名詞作進一步解釋的。例如： 1． We heard the news that he had told her. 我們聽到他對她說的消息。 2． We heard the news that he had won the game. 我們聽到消息他贏得了比賽。 例1中的that從句的作用相當(dāng)于一個形容詞，其作用是修飾the news；例2中的that從句的作用相當(dāng)于一個名詞，是對the news的進一步說明。 二、定語從句的引導(dǎo)詞在從句中充當(dāng)一定的成分，可作主語、賓語、狀語等；而同位語從句中的引導(dǎo)詞在從句只起連接作用，不作任何句子成分。例如： 1. A plane is a machine that can fly. 飛機是一種能飛的機器。 2. The fact that they didn't finish the work has to be faced. 必須面對事實，他們沒有完成工作。 例1中的引導(dǎo)詞that在從句中充當(dāng)句子成分，作從句的主語，故為定語從句；例2中的that只起連接作用，引導(dǎo)從句解釋fact的內(nèi)容，不作任何句子成分，故為同位語從句。 三、引導(dǎo)定語從句的關(guān)聯(lián)詞在從句中作賓語或狀語時，可以省略或被其他詞代替；而同位語從句的引導(dǎo)詞一般不能省略，更不能被代替。例如： 1. The news that she heard is true. 她聽到的消息是真的。 2. The news that she will go abroad is true. 她將出國這消息是真的。 例1是定語從句，that可省略；例2是同位語從句，that不能省略。 3. The reason why he was chosen remains unknown. 他為什么被選上的原因還是不清楚。 4. The idea why he was chosen attracted our attention. 他為什么會被選上，這一想法引起我們的注意。 例3中why引導(dǎo)的是定語從句，why可以被 for which或 that 代替；例4中 why引導(dǎo)的是同位語從句，why 不能省去，也不能被其它詞代替。 四、同位語從句與其所修飾的名詞之間是一種同位關(guān)系，二者之間存在邏輯上的系表關(guān)系，可用“主+系+表”結(jié)構(gòu)來表示。例如： The news that he won the first place is true. 他贏得冠軍的那個消息是真的。 上句若用“主+系+表”結(jié)構(gòu)來表示，則是： The news is that he won the first place. 消息是他贏得了冠軍。 意思合理，系表結(jié)構(gòu)成立，故為同位語從句。 五、定語從句所修飾、限定的先行詞可以是各類名詞，可以有復(fù)數(shù)形式；而同位語從句一般都與抽象名詞同位，一般沒有復(fù)數(shù)形式。例如： 1. The possibilities that she was offered seemed very great.她得到的可能性似乎大些。 2. Her mother was worried about the possibility that her daughter dislike to go to school. 她的母親很擔(dān)心，她女兒有可能不喜歡上學(xué)。 例1中的possibilities是定語從句的先行詞，可用復(fù)數(shù)形式；例2中的possibility是抽象名詞，后接的是同位語從句，一般不用復(fù)數(shù)形式。 六、由when, why, where引導(dǎo)的定語從句分別修飾或說明表示時間、原因或地點的詞，但它們引導(dǎo)的同位語從句一般不和表示時間或地點的詞同位。例如： 1. I still remember the day when I first came to Beijing. 我仍然記得初次來北京的那天。 2. I have no idea when she will be back. 我不知道她何時回來。 3. This is the house where I lived two years ago. 這是我兩年前住的房子。 4. The question where we shall have a meeting hasn't decided. 我們到什么地方去開會，這個問題沒有決定。 例1、3中的when和 where引導(dǎo)的是定語從句，day 和house分別表示時間和地點；例2、4中的when和 where引導(dǎo)的是同位語從句。 如果在定語從句與同位語從句的學(xué)習(xí)中能把握住上述幾種區(qū)別，那么在閱讀文章時，就會迎刃而解，收到更好的效果。 謝謝 祝你學(xué)習(xí)進步
順其自然0012
在定語從句中，that 關(guān)系代詞（在句中作主語、賓語或定語）1.只能用that作為定語從句的關(guān)系代詞的情況a) 在不定代詞，如：anything, nothing, everything, all, much, few, any, little等作先行詞時，只用that，不用which。 All that is needed is a supply of oil. Finally, the thief handed everything that he had stolen to the police. b) 先行詞有the only, the very, the just修飾時，只用that。 He is the very man that helped the girl out of the water . c) 先行詞為序數(shù)詞(the last)、數(shù)詞、形容詞最高級時，只用that。. The first English book that I read was “The Prince and the Pauper” by Mark Twin . d) 先行詞既有人，又有物時。 He talked about the teachers and schools that he visited . e)當(dāng)主句是以who 或which 開始的特殊疑問句時，用that 以避免重復(fù)。 Who is the person that is standing at the gate . f)關(guān)系代詞在從句中做表語 He is not the man that he used to be . 1）不用that的情況a) 在引導(dǎo)非限定性定語從句時 b) 介詞后不能用
順宏冷暖-MISS馮
That可以引導(dǎo)名詞性從句，狀語從句和強調(diào)句。
It was exactly what I needed是表語從句，是"主句+表語從句"構(gòu)成的主從復(fù)合句,其中表語是由"what"引導(dǎo)的是表語從句來充當(dāng).這里"it" 作代詞,當(dāng)然"it"也可替代后面的名詞從句放在句首作形式主語,但這里卻不成。
that名詞性從句。
①引導(dǎo)賓語從句。及物動詞后的引導(dǎo)詞that可省略。
I didn't expect (that) he could win the championship.
The teacher pointed out that Tom was not working hard enough.
② 引導(dǎo)主語從句。通常采用it作形式主語的句型。
That the earth goes around the sun is known to everyone.
（It is known to everyone that the earth goes around the sun.）
③引導(dǎo)表語從句。
The trouble is that we are short of money.
④引導(dǎo)同位語從句。
引導(dǎo)同位語從句的that和引導(dǎo)定語從句的that是不同的。前者只起語法作用，在從句中不作任何成分；而后者在定語從句中作主語、賓語或表語。舉例說明：
The news that he resigned from office surprised us.
The idea that he holds is very common nowadays on campus.
擴展資料：
與that 有關(guān)的常見重要短語。
1、in that，意為“既然、因為”。
Criticism and self-criticism is necessary in that it helps us correct our mistakes.
2、now that，意為“既然、由于”。
Now that they have taken matters into their hands, the pace of events has quickened.
3、see (to it) that，意為“注意、務(wù)必做到、保證”。
We will see to it that she gets home early.
See to it that you are not late again.
4、seeing that，意為“鑒于、由于”。
Seeing that it is 8 o'clock, we'll wait no longer.
Seeing that he was busy with his work, I didn't disturb him.
參考資料：that-百度百科
gell墨脫
that在定語從句中做主語、表語或賓語,作賓語時可省略.必須用that的情況：先行詞有人又有物先行詞有形容詞最高級修飾先行詞是不定代詞先行詞有不定代詞修飾以who,which開頭的問句先行詞有the very, the same ,the last等詞修飾先行詞有序數(shù)詞,數(shù)詞修飾時.關(guān)系詞在定語從句中做表語時不能用that的情況：介詞+關(guān)系詞非限定性定語從句舉例：Is this the book that you borrowed in the library?這是你在圖書館借的那本書嗎?Who that break the window should be punished． 誰打碎了窗戶都要受到懲罰． All that is needed is a supply of oil. 所需的只是供油問題. Finally, the thief handed everything that he had stolen to the police. 那賊最終把偷的全部東西交給了警察.
搖滾喵喵
that從句用法如下：
一、引導(dǎo)名詞性從句
即引導(dǎo)主語從句、賓語從句、表語從句和同位語從句，that沒有任何意義，也不作任何句子成分，只起引導(dǎo)作用。
1. 引導(dǎo)主語從句
由于中英語言文化的差異，漢語沒有主語從句。如，“英語很重要不是人人都認同的?！睗h語語法認為，“英語很重要”是主位詞組做句子的主語。
而英語句子“That English is of vital importance is not acknowledged by all.”中，That English is of vital importance是主語從句。雖然that沒有任何意義，也不作任何句子成分，只起引導(dǎo)作用，但是卻不能省略。如：
That English teacher can speak fluent English is a fundamental requirement.
2. 引導(dǎo)賓語從句
引導(dǎo)賓語從句的that一般可以省略，但在以下六種情況下，一般不能省略。
（1）兩個以上的賓語從句并列時，從第二個從句開始，that 不能省略。如：
Jack was informed（that）he had been enrolled in Sun Yat-sen University，and that he should register by August.
（2）介詞后引導(dǎo)賓語從句的that 不能省略。如：
His parents expected him nothing but/except that he can make a living by himself after graduation.
（3）主句的謂語動詞與that引導(dǎo)的賓語從句之間有插入語時，that不可省略。如：
The head teacher told Jack， after a short hesitation， that he could have a day off on condition that he could make up for the missing lessons.
（4）形容詞后引導(dǎo)賓語從句的that一般不省略。如：
Marys parents are very content that their daughter has made such great progress in the final examination.
（5）在 it（形式賓語）+ adj.（補足語）+ that（賓語從句）結(jié)構(gòu)中， that不能省略。如：
Everyone believes it strange that he could pass the driving test.
（6）在直接引語中，that引導(dǎo)的賓語從句與主句隔開時，that不能省略。如：
“Im sorry to say，” he said， “that you are not the suitable person for the work.”
3. 引導(dǎo)表語從句
表語從句位于連系動詞后，引導(dǎo)表語從句的that一般不能省略。如：
My advice is that everyone be punctual for the appointment.
特別注意：下列句式中的that一般不能用because代替。
The reason why he was late for school is that he missed the early bus.
4. 引導(dǎo)同位從句
同位語從句就是在news， information， fact， word， idea等抽象名詞之后，說明其具體內(nèi)容的從句。引導(dǎo)同位語從句的that一般不能省略。如：
Based on the fact that you are enthusiastic about Chinese culture， Im writing to invite you to get involved in it.
二、引導(dǎo)定語從句
that常被用來代替關(guān)系代詞which或who，引導(dǎo)定語從句。以下幾種情況，多用that而不用which或who。
1. 當(dāng)先行詞是表示事物的all， any， anything， everything， nothing或被all， any， every等修飾時。如：
Do you have anything that you are puzzled with？
All that can be done must be done.
2. 當(dāng)先行詞被形容詞的最高級或序數(shù)詞修飾時。如：
It is one of the most touching movies that have been shown this month.
The first thing that we should do is to get some food.
3. 當(dāng)先行詞有the only， the very， the same， the last 等修飾時。如：
The only thing that is impressive is his unforgettable experience in Beijing.
4. 當(dāng)主句以who或which開頭的疑問句時。如：
Who is the girl that is delivering a speech over there？
5. 當(dāng)先行詞既有人又有物時。如：
The writer and his novel that you have just talked about are really well known.
三、引導(dǎo)狀語從句
1. that 可引導(dǎo)目的狀語從句和結(jié)果狀語從句，that一般不省略。如：
The story is so touching that we will bear in our mind for a long period.
An English Speech Contest will be organized so that/ in order that students can improve their oral English.
sjloveyuliqin
That可以引導(dǎo)定語從句 ?、名詞性從句 ?、狀語從句 ?。
that是表語從句。
技巧：判斷是什么從句，就是看從句在整個句子中做什么成分，顯然是在整個句子“It was exactly
某某”中做was的表語。當(dāng)然，是what引導(dǎo)從句，在從句中充當(dāng)賓語成分，為need的賓語。
擴展資料：
1、(引導(dǎo)名詞性從句)
He expressed the hope that we would keep in touch with his firm.他表示希望我們與他的公司保持聯(lián)系。
My idea is that we should act on his suggestion.我的意見是我們應(yīng)當(dāng)按照他的建議去辦。
That she is still alive is a relief. 她還活著,這是令人感到寬慰的。
2、(引導(dǎo)狀語從句,表示原因或理由)因為,由于
We are glad that we have accomplished another arduous task. 我們都感到高興因為又完成了一項艱巨的任務(wù)。
3、(引導(dǎo)狀語從句,表示目的或結(jié)果)為了,以至于
He is working hard that he can catch up with the class. 他努力用功,以便趕上班上同學(xué)。
4、(引導(dǎo)表示愿望,感嘆的從句,主句常省略)
ThatI could stay at home today! 今天要是我能呆在家里多好呀!
參考資料：百度百科——that
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