分別在句中作主語、賓語、表語及同位語。
名詞性從句講解
在主從復合句中，從句可以充當主句的主語、表語、賓語或同位語。由於在多數情況下，主語、表語、賓語或同位語這四種句子成分由名詞性詞類充當，所以，我們把這些作用相當於名詞的從句統稱為名詞性從句，把充當主語、表語、賓語或同位語的從句分別稱為主語從句、表語從句、賓語從句或同位語從句。也就是說充當什麽成分就叫什麽從句。名詞性從句由連接詞（或關聯詞）引導。常用的連接詞有：
連接詞
作用
whether 是否
that (本身無詞義)
只起連接詞作用，引導從句，在從句中不作任何成分
who, whom, whose
which 哪壹個
what 什麽，所…的
在從句中分別作主語、賓語和定語
在從句中分別作主語、賓語和定語
在從句中分別作主語、賓語和定語
when什麽時候，where什麽地方
how怎樣、怎麽，why為什麽
除了起連接詞作用外，還在從句中作狀語
疑問詞（who, whom, whose, what, which, where, why, when, how）可以引導主語、賓語和表語從句。它們的特點是：1、疑問詞有本身的詞義；2、疑問詞在從句中擔當句子成分，如主語、賓語或狀語；3、這種疑問詞引導的從句壹律用陳述語序，不能用疑問語序。
For example:
Do you know whom they are looking for? 妳知道他們在找誰嗎？（賓語從句，陳述語序。不能是whom are they looking for?）
I don’t know who did it.我不知道這是誰幹的。（賓語從句。在從句中如果疑問詞作主語，其陳述語序和疑問語序壹致。）
She asked me where I had been.她問我到哪兒去了。（賓語從句。陳述語序，不能是where had I been. 直接引語，間接引語。註意這句話的時態。）
Can you tell me when the train will arrive? 妳能告訴我火車什麽時候到嗎？(賓語從句。陳述語序，不能是when will the train arrive. 直接引語，間接引語。)
I don’t know why he hasn’t come yet. 我不知道他為什麽還沒來。（賓語從句，陳述語序。不能是why hasn’t he come yet.）
He didn’t tell me what you were doing. 他沒和我說妳在幹什麽。（賓語從句，陳述語序。不能是what were you doing.）
What you have done might do harm t other people. 妳所做過的事情有可能傷害別人。（主語從句。what 作從句的賓語。陳述語序，不能是what have you done. 如果用疑問語序，意思發生了變化，成了“妳做了什麽？”。）
I don’t know where he is now. 我不知道他現在在哪裏。（賓語從句，陳述語序。不能是where is he now.）
Where he went for his weekend is not known. 不知道他去哪裏過的周末。（主語從句，where 作從句的地點狀語。陳述語序，不能是where did he go for his weekend.）
Whose fault this is is not important. 這是誰的過錯並不重要。（主語從句，whose 作從句的定語。陳述語序，不能是whose fault is this.）
What I want to know is where he has gone for his weekend. 我想知道的是他到哪裏度周末去了。（這句話包含兩個名詞性從句：what I want to know是主語從句，what 在從句中作賓語，從句用陳述語序，不能是What do I want to know. Where he has gone for his weekend 是表語從句，where 在從句中作狀語，從句用陳述語序，不能是where has he gone for his weekend.）
下面我們再分別講述主語從句、賓語從句、同位語從句和表語從句。
壹、 主語從句
1．that 引導主語從句時，that 沒有意義，但不能省略。（that 引導賓語從句時可以省略。）
For example:
It worried her a bit that her hair was turning gray.她的頭發正在變白，這使她很不安。that引導主語從句，it 作形式主語，that 不能省略。
That she is a rich woman is known to us all. 眾所周知，她是個富有的女人。這是that 引導主語從句，that 不能省略。這句話可以改為用it 作形式主語的句型。請同學們改寫：It is known to us all that she is a rich woman.）
We didn’t know (that) you had sold your house. 我們不知道妳已經把妳的房子賣了。這是that引導賓語從句，that 可以省略。註意這句話的時態。
2．從句作主語時，多數情況下由 it 作形式主語，而把主語從句放在後面，尤其是謂語部分（包括賓語）較短的情況下。
For example:
It wasn’t very clear what she meant. 不清楚她是什麽意思。
It is important that he should come on time. 他按時來是很重要的。
It is true that that man on the left is a well-known writer here. 左邊那個人是本地的壹位著名作家，這是真的。這裏，第壹個that 引導主語從句，是單純的連詞，無詞義，不作句子成分。第二個that 是指示代詞，作句子成分，是man 的定語。
3．whether 既可以引導主語從句也可以引導賓語從句，但if不能引導主語從句。whether 後面可以加or not, 而if 不能與or not 連用。作介詞賓語時不用if.如：
Whether I knew John doesn’t matter. = It doesn’t matter whether I knew John. 我是否認識約翰沒有關系。
Whether or not she’ll come isn’t clear. = Whether she’ll come or not isn’t clear. = It isn’t clear whether …. 她是否來還不清楚。
It all depends on whether we can get their cooperation. 這是主語從句還是賓語從句？it 是形式主語嗎？it 是代詞，whether 引導的是賓語從句，作介詞on 的賓語，不能用if引導。請翻譯這句話。這完全取決於我們是否能得到他們的合作。
I worry about whether I hurt her feelings. 賓語從句，介詞賓語，不能用if 引導。請翻譯這句話。
She asked me whether/if you were married. 賓語從句，既可以用whether, 又可以用if 引導。註意時態的對應。請翻譯這句話。
We haven’t decided whether/if we shall give them aid.
I’m not sure whether/if the report is believable.
Now let’s do some translation:
現在還很難預測誰會贏得下壹屆總統選舉。
It is still hard to predict who will win the next presidential election.
對於多數公民來說，誰當選總統無關緊要。
Who will become the president doesn’t matter much to most citizens.
這位前總統是否會被判處死刑還有待觀察。
It remains to be seen whether the ex-president will be sentenced to death.
真可惜，王教授不能出席我們的英語晚會。
It is a pity that Prof. Wang can’t attend our English Evening.
我們需要的是更多的時間。
What we need is more time.
二、 賓語從句
在謂語動詞、介詞、動詞不定式、分詞、動名詞之後都可以帶有賓語從句。某些形容詞如sure, happy, glad, certain, pleased 等之後也可以帶有賓語從句。
1． that 引導的賓語從句: that 沒有意義，在口語或非正式文體中常省略
例如：
I really feel she’s making a mistake. 我的確感到她正犯錯誤。
James said (that) he was feeling better. 詹姆斯說他感到好些了。
Hearing that his son was badly wounded, he hurried to the hospital to see him.聽說兒子受了重傷，他急忙趕到醫院去看望他。
I suggested that we should go home. 我建議我們回家去。虛擬語氣，that 壹般不能省略。
2．whether/if (是否)引導的賓語從句：如果要突出“究竟是…還是不…”，常在whether 後面加or not; if 壹般不與or not連用。如：
He asked me if/whether I knew John. 他問我是否認識約翰。
Let me know whether you can come or not. 妳能來還是不能來，告訴我壹聲。
3．在think, believe, suppose, expect 等動詞的賓語從句中，否定不用在從句中，而是將think 等詞變為否定形式。For example:
I don’t think the film is interesting.我覺得這部電影沒什麽意思。
I don’t suppose we are going outing tomorrow. 我認為我們明天不會出去郊遊。
4．如果從句作賓語而後面還有補語，為了保持句子的平衡，用it 作形式賓語，而將賓語從句放在句尾。常跟這樣的復合賓語的動詞有：make, find, see, hear, feel, think, consider, regard, take….for granted等。如：
George made it clear that he opposed this project. 喬治已明確表示他反對這個項目。it 代表that 引導的句子，作賓語，clear 是賓語補足語。
They kept it quiet that he was dead. 對他已經死亡的消息，他們秘而不宣。
I took it for granted that you’d stay with us. 我想當然認為妳會和我們呆在壹起。
三、 同位語從句
同位語從句是對名詞的內容給予具體、詳細的說明。常在後面接同位語從句的名詞有fact, news, idea, truth, hope, suggestion, question, problem, doubt, fear, belief等。同位語從句常用的引導詞為that,有是也用when, where 等疑問詞。
如：
The news that the United States was hit by terrorist attacks took the whole world by surprise. 美國受到恐怖主義分子襲擊的消息令全世界吃驚。
The idea that you can do this work well without thinking is quite wrong.妳認為不動腦筋就能做好這件工作的想法是完全錯誤的。
People used to hold the belief that the earth was the center of the universe. 人們曾認為地球是宇宙的中心。
The difficulty lies in the fact that we are short of money.困難在於我們缺乏資金這個事實。
They have no idea at all where he has gone.他們壹點兒也不知道他去哪兒了。
註意：同位語從句的that 只是引導詞，沒有其他語法作用，在句子中不作句子成分，不能省略；而定語從句中的that 除了引導定語從句外，還是定語從句的壹個成分，在定語從句中作主語或賓語，作主語時不能省略，作賓語時可以省略。
如：
The idea that some peoples are superior to others is sheer nonsense.有些民族優越於其他民族這種想法簡直荒謬。（請辨別是同位語從句還是定語從句。）（同位語從句）
The idea that he proposed at the meeting is sheer nonsense. 他在會議上提出的這個想法簡直荒謬。（請辨別是同位語從句還是定語從句。）（定語從句）
No one is happy with the fact that he found out. 沒有人對他發現的事實感到高興。（請辨別是同位語從句還是定語從句。）（定語從句）
No one is happy with the fact that he will become their boss.沒有人對他將成為他們的老板這壹事實感到高興。（請辨別是同位語從句還是定語從句。）（同位語從句）
四、表語從句
表語從句位於主句的連系動詞之後，在非正式文體中引導詞that可以省略。如：
That’s not what I want. 那不是我要的。
That’s why I have come.那就是我為什麽來了。
My opinion is that things will improve.我的意見是事情會好起來的。
One advantage of solar energy is that it will never run out. 太陽能的壹個優點是永遠也不會枯竭。
The truth is that he didn’t really try. 實際情況是他沒有真正努力。
The problem is who is to pay and when we can start.問題是誰來付帳、我們又何時開始。
The fact is that he didn’t notice the car until too late. 事實是他註意到車時已經太晚了。
What surprised me was that he spoke English so well.使我感到吃驚的是他英語講得那麽好。
All I can say is that I have nothing to do with it. 我能說的就是我與此事沒有關系。
What I want to know is where we shall go and whether she will join us. 我想知道的是我們要去什麽地方以及她是否加入我們。
此外，表語從句還可由as if （好像）引導。如：
It looked as if it was/were going to rain. （虛擬語氣）
Now let’s do some translation:
這就是她昨天請壹天假的原因。
That is why she had a day off yesterday.
我的想法是，個人的權利應該得到充分尊重。
My idea is that individual rights should be fully respected.
問題在於上帝是否真的存在。
The question is whether the God really exists.
我想知道的是，他是如何在這麽短的時間內完成這個項目的。
What I want to know is how he managed to complete the project in such a short time.
五、形容詞後的that 從句
that 引導的名詞性從句還可以用在壹些形容詞後面。這種句型壹般都用人作主語，所用的形容詞都是表示思想狀況或感情色彩的形容詞，如certain, sure, positive, afraid, convinced, anxious, disappointed, worried, glad, happy, sorry, amazed, surprised, aware, doubtful, confident等等。
如：
I am sure/certain that he’s at home now.我肯定他現在在家。
He became angry that you made the same mistake. 妳犯了同樣的錯誤，他生氣了。
He remains confident that he will win. 他仍然自信他會贏
She is aware that I can’t help her. 她知道我幫不了她的忙。
I am glad that you’ve come. 妳來了我很高興。
He appeared/seemed surprised that I said “no”. 我說不，他似乎很吃驚。
I am afraid that I can’t promise you anything. 恐怕我不能向妳保證什麽。
We were rather disappointed that you were not able to come yesterday. 昨天妳沒能來我們有點失望。
I am a bit worried that she will not be able to make it. 我有點擔心她做不成這件事情。
六、what 從句的小結
1． 意思是“所….的事/物”, 相當於the thing(s) that…, that which…, 或those which… 可以用於以下情況：
(1) 引導主語從句。如：
What she saw frightened her. 她看到的事情嚇了她壹跳。
What was once regarded as impossible has now become a reality. 曾經被認為不可能的事情，現在已經變成了事實。
What I’m afraid of is their taking him to that place. 我怕的是他們帶他到那地方去。
What we are worrying about is just her innocence. 我們擔心的是她的幼稚。
But what hurt our feelings most was the personal comment of the judge. 最傷我們感情的是法官的私下評論。
What will be, will be. 要發生的事總是要發生的。（諺語）
What is gone is gone. 過去的事就過去了。
(2) 引導表語從句。如：
That’s what I hope. 那就是我希望的。
I should like to be a teacher. That’s what I want to be. 我想當老師，那是我想幹的事。
Times are not what they used to be. 時代不同了。
He’s not what he was a few years ago. 他不是幾年前的他了。
Your health is not what it ought to be. 妳的身體應該更好。
(3) 引導賓語從句，包括介詞賓語。如：
He could not express what he felt. 他不能表達他的感受。
Well, I’ll do what I can. 好吧，我盡力。
I can’t do what you’ve just asked of me. 我不能做妳剛才要求我的事。
And having got what he wanted, he took his hat and went away. 得到了他要的東西，他拿上帽子就走了。
As a friend of yours, I want to tell you what I hear. 作為妳的朋友，我想告訴妳我所聽到的。
The father began to criticize what the boy had done. 父親開始批評男孩所做的事。（註意時態）
She was not happy at what he had said. 她對他說的話不高興。
Don’t poke your nose into what doesn’t concern you. 不要多管閑事。
The city is different from what it was ten years ago. 這座城市和十年前不同了。
It was a small place then compared to what it is now. 和現在比起來，它那時候是個小地方。
I don’t care about money or what people call position. 我不在乎金錢或者別人所謂的地位。
Philip was depressed by what he had gone through. Philip經歷過的事情使他很消沈。
They paid fifty percent of what they were able to earn to the state.
他們能掙來的東西，百分之五十交給了國家。
2． 用作插入語，指代後面的成分。這和非限定性定語從句正好相反，非限定性定語從句指代的是前面的成分。如：
Then I discovered, what was news to me, that his wife was Mary’s niece. 後來我發現，他妻子原來是Mary的侄女，這對我是個新聞。
He never joined in the usual sports of the boys, and, what is remarkable, never went out in a boat on the river. 他從來不參加男孩子通常做的體育活動，更奇怪的是，他從來不坐船出去到河上面去。
He’s an interesting speaker, and, what is more important, he knows his subject thoroughly. 他講話生動有趣，更重要的是，他對課題了如指掌。
He went to the meeting and, what was worse, insisted on speaking. 他去參加了會議，而且更糟糕的是，他堅持要發言。
It is a useful book, and, what is more, not an expensive one. 這是本很有用的書，再說也不貴。
You’ll have nobody but yourself to blame, and, what’s more, you’ll get no sympathy from anybody. 妳怪不著別人，只能怪妳自己；還有，妳得不到任何人的同情。
We invited a new speaker and, what’s more, he was happy to come. 我們請到了壹位新的發言人，而且他很樂意來。
3． 引導讓步狀語從句，等於“不管什麽…”。註意狀語從句的語序。如：
Do what she would, she could not invent a reason for not going. 不管她會做什麽，她都編不出不去的理由。狀語從句把實義動詞放在句首，句子倒裝。＝No matter what she would do, …
Come what may, you’ll always keep it secret. 無論怎樣，妳都要保守秘密。＝No matter what may come, ….
Jack has made up his mind that, come what might, he would stay there. Jack已經拿定主意，無論如何他也要呆在那裏。＝…no matter what might come, …
Say what he will, in his heart he knows that he is wrong. 不管他怎麽說，內心裏他知道自己錯了。= No matter what he will say, …
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