李向陽

名詞性從句（Noun Clauses）學習要點：

名詞性從句（Noun Clauses），顧名思義，在句子中起名詞的作用。它在復合句中能擔任主語、賓語、表語、同位語，根據(jù)它在句子中不同的語法功能，名詞性從句又可分別稱為主語從句、賓語從句、表語從句和同位語從句。

主語從句（The Subject Clause）

主語從句在復合句中作主句的主語。引導主語從句的詞有連詞that，whether；連接代詞who，what，which，whatever，whichever；連接副詞when，where，how，why等。

That she was chosen made us very happy.

Whether she will come or not is still a question.

Which team will win the match is still unknown.

How he became a great scientist is known to all of us.

Why he did it wasn't quite clear？

Is what you told me really true？

主語從句放在句首，句子常顯得笨重，因此通常把它移到句子后面，主句中用引導詞“it”來作形式主語。

It's a pity that she has made such a mistake.

It's strange that he didn't come yesterday.

連接代詞who，what，which和連接副詞when，where，how，why等引導的主語從句可簡化成連接代詞或連接副詞加不定式的簡略形式，有時也可轉(zhuǎn)換為定語從句。

How they can learn English well is a question which often confuses some students.

相當于：How to learn English well is a question which often confuses some students.

What we need is time.

相當于：The thing （which/that） we need is time.

在“It's...that...”的句型中，當表示講話者明確的建議或表示講話者“驚訝、惶恐”的語氣時，that從句要用“（should） do”的動詞形式。例如：

It's necessary that we （should） read English every day.

It's surprising that the girl （should） marry so early.

It's suggested that the road （should） be repaired at once.

賓語從句（The Object Clause）

賓語從句在復合句中作主句的賓語。引導賓語從句的詞與引導主語從句的詞一致。另外，連詞if也可引導賓語從句。在賓語從句中，連詞that可以省略。同樣，連接代詞who，what，which和連接副詞when，where，how，why等引導的賓語從句，賓語從句可簡化成連接代詞或連接副詞加不定式的簡略形式，有時也可轉(zhuǎn)換為定語從句。簡單地說，把主語從句放到賓語從句的位置上，主語從句就演變成賓語從句了。

I hear （that） westerners always have difficulty in learning Chinese.

Could you tell me how I can get to the post-office？

相當于：Could you tell me how to get to the post-office？

We will use what we have to buy you a dress.

相當于：We will use the money （which/that） we have to buy you a dress.

He insisted that he had not stolen the money and that he （should）be set free at once.

表語從句（The Predicative Clause）

表語從句在復合句中作主句的表語，置于連系動詞后面。引導表語從句的詞有連詞that，whether，as if（好像，仿佛）；連接代詞who，what，which；連接副詞when，where，how，why等。同樣，連接代詞who，what，which和連接副詞when，where，how，why等引導的表語從句，表語從句可簡化成連接代詞或連接副詞加不定式的簡略形式。

The question is whether the book is worth reading at all.

That is where he was born.

It seems that all of the students have done their homework.

It looked as if it was going to snow.

The problem is how to prevent the pollution to live happily.

His suggestion is that the road （should） be repaired at once.

連詞as if常和look，seem，sound搭配，構(gòu)成look as if，seem as if，sound as if。as if引導的表語從句如果表示的是事實，就用陳述語氣；反之，要用虛擬語氣。

The dark clouds are gathering.It looks as if there will be a big storm.

He looked as if he were a spirit in that funny suit.

另外，because也可以引導表語從句。在英語中有“It（This/That） is because...”的句型。例如：

The earth looks blue from space.This is because 70% of the surface is covered by water.

同位語從句（The Appositive Clause）

同位語從句一般跟在名詞news，answer，hope，fact，belief，evidence，idea，promise，information，conclusion，order，suggestion，problem，thought，possibility等后面，用來說明名詞所表示的具體內(nèi)容。引導同位語從句的詞有連詞that；連接副詞when，where，how，why等。連接副詞when，where，how等引導的同位語從句可簡化成連接副詞加不定式的簡略形式。

I have no idea when she will be back.

She told us her hope that she would become a pianist.

He made a promise that he would never come late.

He always works hard even if he knows the fact that he is in poor health.

They all subscribed to his suggestion that the school （should） be built at once.

that既可引導同位語從句又可引導定語從句，其區(qū)別在于：同位語從句由連詞that引導，連詞that本身無意義，在同位語從句中不充當任何成分，不可省略；定語從句由關(guān)系代詞that引導，關(guān)系代詞that在從句中充當一定的成分，作賓語時可省略。由when，why，where引導的同位語從句和定語從句的區(qū)別在于：同位語從句中的連接副詞只起連接作用，沒有指代前面名詞的作用；定語從句由關(guān)系副詞引導，關(guān)系副詞具有指代先行詞的作用，常用一個介詞加關(guān)系代詞替換。

We know the fact that he is a thief.（同位語從句）

He collected the facts that/which prove the earth turns around the sun.（定語從句）

The policeman had to work out the problem how he got so much money.（同位語從句）

It's the problem which/that will be discussed at tomorrow's meeting.（定語從句）

名詞性從句（Noun Clauses）專項練習

1.The truth is________he doesn't make good use of time in class.

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

2.The reason why he was late was________he had taken a wrong bus.

A.because B.whether C.why D.that

3.Einstein's most famous theory is________we call the Theory of Relativity.

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

4.Please find out when________get to Nanjing.

A.will the train B.would the train C.the train will D.the train would

5.We have plenty of books here.You may take________you like most.

A.which B.whatever C.whichever D.that

答案 CDACC