同位語從句和定語從句很相似，但還是有區(qū)別的，區(qū)別主要在以下三方面：

1. 從詞類上區(qū)別

同位語從句前面的名詞只能是

idea，fact，news，hope，belief，suggestion，proposal，word，thought，doubt，truth，possibility，promise，order等有一定內(nèi)涵的名詞，而定語從句的先行詞可以是名詞、代詞、主句的一部分或是整個主句。如：

The possibility that the majority of the labour force will work at home is often discussed.人們經(jīng)常討論大多數(shù)勞動力將會在家里工作的可能性 (同位語從句)

We are not looking into the question whether he is worth trusting. 我們正在調(diào)查的問題不是他是否值得信賴的問題 (同位語從句)

Word came that he had been abroad. 據(jù)說他已經(jīng)出國了 (同位語從句)

Our team has won the game， which made us very happy. 我們的隊贏了，這讓我們很高興 (定語從句)

The doctor whom you are looking for is in the room. 你找的那位醫(yī)生在房間里面 (定語從句)

His mother did all she could to help him with his study. 他媽媽盡她的最大努力幫助他的學習 (定語從句，代詞all作先行詞?)

2. 從性質(zhì)上區(qū)別

定語從句是從句對其先行詞的修飾或限制，屬于形容詞性從句的范疇;而同位語從句是從句對前面抽象名詞的進一步的說明和解釋，屬于名詞性從句的范疇，如：

The news that our team has won the game was true. 我們隊贏了那場比賽的消息是真的 (同位語從句，補充說明news到底是一個什么消息)

The news that he told me yesterday was true. 昨天他告訴我的那個消息是真的 (定語從句，news在從句中作told的賓語)

I made a promise that if anyone set me free I would make him very rich. 我許諾如果誰讓我自由，我就讓他非常富有 (同位語從句，補充說明promise到底是一個什么諾言)

The mother made a promise that pleased all her children. 媽媽做出了一個令她的孩子們高興的許諾 (定語從句，promise在從句中作pleased的主語)

3. 從引導詞及其在句子中的成分上區(qū)別

有些引導詞如how， whether， what可以引導同位語從句，但不能引導定語從句，如：

That question whether we need it has not been considered. 我們是否需要它這個問題還沒有考慮 (同位語從句)

I have no idea what has happened to him. 我不知道他發(fā)生了什么事 (同位語從句)

引導詞that引導定語從句時，在從句中一般作主語或賓語(指物時還可以用which代替)，并且作賓語時常常省略that在同位語從句中僅起連接作用，不充當任何成分，并且不能省略，也不能用which來代替如：

The order that we should send a few people to help the other groups was received yesterday. 我們應派幾個人去幫別的幾個小組的命令昨天收到了(同位語從句，是對order的具體解釋，that雖不作成分，但不能省略)

The order that we received yesterday was that we should send a few people to help the other groups. 我們昨天收到的命令是我們應該派幾個人去幫助別的幾個小組(定語從句，是名詞order的修飾語，that在從句中作received的賓語，可以省略)

1. There is hard evidence___________George has something to do with the murder.

A.which B.what C.why D.that

2.It is the promise _______ the government will ban students from using mobile phones at school _______ excites the teachers and parents.

A.that, that B.which, that C.不填 ; that D.that, which

3.The information sent by the robots from Mars has offered a scientific proof _______ there existed water on Mars.

A.if B.whether C.where D.that

4.—Is it true that Mike refused an offer from Yale University yesterday?

—Yeah, but I have no idea ____________ he did it; that’s one of his favorite universities.

A. when B. why

C. that D. how

5. The belief,as is a commonly accepted saying ___________ practice makes perfect fails to work wonders if repeated without action.

A.what B.which C.that D.where

參考答案

1. D

2.A

3.D

4.B

5. C