一、名词性从句的结构和功能总述
名词性从句包括主语从句、宾语从句、表语从句和同位语从句。名词性从句是一种具有名词功能的非独立分句。名词性从句主要有四种从句结构:
以 that 引导的从句;
以 whether/if 引导的从句;
以特殊疑问词 who, where, why 等引导的从句;
以 what 或 wh-ever 等引导的名词性从句。
此外, as if/as though 也可引导表语从句。
具体用法见下表:
题组训练 完成下列句子
①Can you tell me how I can (我如何能)get to the railway station?
②These photographs will show you what our village looks/is like (我们村看上去是什么样子的).
二、以 that 引导的从句
(一)主语从句
1. that 从句作主语时, 常用 it 作形式主语, 常见的句型有:
(1) It + be + 形容词(obvious, true, natural, surprising, good, wonderful, funny, possible, likely, certain, probable, etc.) + that 从句。
It is certain that she will do well in her exam.
可以肯定她会考得很好。
It is probable that he told her everything.
很可能他把一切告诉了她。
(2)It + be + 名词(词组)(no wonder, an honor, a good thing, a pity, no surprise, etc.) + that 从句。
It's no surprise that our team has won the game.
我们队已经赢了那场比赛并不令人惊奇。
(3) It + be + 过去分词( said, reported, thought, expected, decided, announced, arranged, etc.) + that 从句。
It is said that Mr. Green has arrived in Beijing.
据说格林先生已经到北京了。
It is decided that the meeting has been put off till next Monday.
已经定下来了, 会议推迟到下周一了。
2. 在口语中, that 常可省略, 尤其是在非常短的句子中, 但that 从句位于句首时, that 是不能省略的。
It's a pity (that) you're leaving. 你要离开, 真遗憾。
That we are invited to the concert this evening is good news to us.
我们被邀请去参加今晚的音乐会, 这对我们来说是个好消息。
(二)宾语从句
1. 常见的可以接 that 从句作宾语的动词有 see, say, know, imagine, discover, believe, tell, show, think, consider 等。在可以接复合宾语的动词(如: think, make, consider 等)之后, 可以用it 作形式宾语。
Do you know (that) he has joined the army?
你知道他参军了吗?
We think it highly probable that he is dead.
我们认为他很可能死了。
We consider it necessary that he should improve his pronunciation.
他应当改进他的发音, 我们认为这是必要的。
He has made it clear that he will not give in.
他不会屈服的, 这一点他已明确表示了。
2. that 从句一般不能充当介词宾语, 偶尔可作except, in 的宾语。
He is a good student except that he is a little bit careless.
他是个好学生, 就是有点粗心。
He differed from his classmates in that he devoted his spare time to reading. 他和他的同学不同的地方在于他把空闲时间用在了读书上。
其他介词后面需要用that 从句作宾语时, 需用it 作形式宾语。
You may depend on it that I shall always help you.
你可以相信我会一直帮助你的。
(三)表语从句
that 引导表语从句时, 一般不省略。
My decision is that all of us are to start at 6 o'clock tomorrow morning.
我的决定是我们所有人明天早上6 点出发。
(四)同位语从句
that 引导同位语从句时, 用在某些抽象名词( 如: fact, hope, desire, thought, suggestion, idea, news, problem, possibility 等)之后, 对前面的名词起补充说明的作用, that 只起引导同位语从句的作用, 在从句中不充当任何成分, 一般不省略。
There's a feeling in me that we'll meet again.
我有一种感觉, 我们会再见面。
(五)that 引导的同位语从句与that 引导的定语从句的区别
that 引导同位语从句时, 应放在某些抽象名词(如: news, word(消息), idea, fact, hope, desire, thought 等)之后, 对前面的名词起补充说明的作用, that 在从句中不充当任何成分, that 引导的同位语从句是完整的, 不缺任何成分。
that 引导定语从句时, 一方面起引导定语从句的作用, 另一方面, that 在定语从句中充当主语、宾语或表语。因此, that 引导的定语从句的成分是残缺的。
The news that our football team won the match was encouraging.(同位语从句, 不缺任何成分)
我们足球队赢了那场比赛的消息令人鼓舞。
The news (that) we heard on the radio was not true.(定语从句, 缺少宾语)
我们在收音机里听到的那则消息不是真的。
题组训练 单句填空
③It is obvious to the students that they should get well prepared for their future.
④The news that we are having a holiday tomorrow is not true.
三、以 whether/if (是否) 引导的从句
(一)表语从句和同位语从句常用 whether 引导不用 if; 当主语从句放于句首时, 也常用 whether 引导不用 if;当 it 作形式主语, 主语从句放在后面时, 用 whether 或 if 引导均可, 但是如果被后置的主语从句中含有表选择意义的 or not 时常用 whether。
Whether the meeting will be held is still a problem.(主语从句放于句首)
是否要举行会议仍然是一个问题。
The problem is whether the meeting will be held.(表语从句)
问题是是否要举行会议。
I have no idea whether the meeting will be held.(同位语从句)
我不知道这个会议是否会举行。
It is doubtful whether/if he will come here.(主语从句放于句尾)
他是否要来这儿还很难说。
(二)在宾语从句中
1. 在及物动词后
(x)I don't care whether he doesn't come.(whether 从句中不能用否定式)
(√)I don't care whether/if he comes or not.
(√)I don't care whether or not he comes.
(x)I don't care if or not he comes.(if 不与 or not 直接连用)
(√)I don't know whether to go there.
2. 在介词后
在介词后常用whether, 不用if。
It depends on whether you can do the work well.
那取决于你是否能做好这项工作。
题组训练 用whether/if 填空
⑤It is still under discussion whether the old bus station should be replaced with a modern hotel or not.
⑥I am not sure whether/if he will come here or not.
⑦This decision will have effect on whether or not he will succeed.
四、连接代/副词引导的从句
(一)主语从句
连接代/副词引导主语从句时, 常用it 作形式主语。
It makes no difference where we shall have the meeting.
我们在哪儿∙∙开会都无所谓。
It has not been decided yet who will preside over the meeting. 由谁∙来主持会议还没有决定。
(二)宾语从句
1. 能接连接代/副词引导的宾语从句的动词有很多, 常见的有 see, tell, ask, know, decide, imagine, suggest, doubt, wonder, show, discuss, understand, inform, advise 等。
I can't imagine how he did it.
我不能想象他是如何∙∙做的这件事。
They couldn't understand why I refused it.
他们不明白我为什么∙∙∙拒绝。
2. 作介词宾语。
It all depends on how we solve the problem.
这完全要看我们如何∙∙解决这个问题。
We are worrying about what we should do next.
我们正在为下一步该做什么∙∙而烦恼。
(三)表语从句、同位语从句
The problem is where we should stay.
问题是我们应该待在哪里∙∙。(表语从句)
My question how I shall get in touch with him has not been answered.
我如何∙∙能和他取得联系的问题还没有得到答复。(同位语从句)
题组训练 单句填空
⑧ I'm afraid he's more of a talker than a doer, which is why he never finished anything.
⑨Many young people in the West are expected to leave what could be life's most important decision—marriage—almost entirely up to luck.
五、以 what 或 wh-ever 等引导的名词性从句
what 可用来引导名词性从句, 此时what = the thing(s) which/that, 有时what 可以用作前置定语, 如 what help, what funny stories 等。此外, whoever = anyone who; whichever = anyone who/anything that (whichever 也可指人); whatever = anything that (whichever 和 whatever 也可作定语)。有时 where( = the place where) 和 when( =the time when)也可以用来引导名词性从句。
(一)主语从句
What they need is a good textbook.
他们需要的是一本好课本。
Whatever he likes will be given to him.
他喜欢的任何东西都会给他。
Whichever book he bought would be paid for.
无论他买了哪一本书都要付款。
Whoever did this job must be rewarded.
无论谁干了这项工作一定要得到酬谢。
(二)宾语从句
She will give whoever ( = anyone who ) needs help warm support.
凡需要帮助的人, 她都会给予热情的支持。(作动词宾语)
I spent what little time I had with my family.
我仅有的那一点时间都与家人在一起度过了。(作动词宾语)
She walked up to where ( =the place where)he stood.
她走到他站着的地方。(作介词宾语)
I can judge by what ( =the things that)I know of him.
我可以根据我对他的了解来判断。(作介词宾语)
You can write about whatever topic ( = any topic that) you prefer. 你可以写你喜欢的任何题目。(作介词宾语)
(三)表语从句
This is where our problem lies.
这就是我们的问题所在。
Tomorrow is when it would be the most convenient.
明天是最方便的时候。
(四)同位语从句
I gave the girl a big doll, exactly what she longed to have.
我给了这个女孩一个大洋娃娃, 那正是她渴望拥有的东西。
(五)宾语补足语
We'll make him whatever he is fit for.
他适合干什么, 我们就培养他干什么。
I'll call the baby whatever name you like.
你喜欢什么名字, 我就叫这个小孩什么名字。
He has made the company what it is today.
他把公司办成了今天这个样子。
题组训练 单句填空
⑩(2013 江西, 30) Whichever one of you breaks the window will have to pay for it.
[11]The book can be of help to whoever wants to do the job.
[12] She is very dear to us. We have been prepared to do whatever it takes to save her life.
[13]—How about camping this weekend, just for a change? —OK, whatever you want.
[14] To improve the quality of our products, we asked for suggestions whoever had used the products.
六、名词性从句的几个易混点
(一)that 通常不可省略的情况
1. that 引导的主语从句置于句首时;
That prices will go up is certain.
物价要上涨是肯定的。
2. 当一个句子有两个或多个并列的宾语从句时, 引导第二个和以后几个从句的that 不可省略;
He told me he had to leave and that he would be back soon.
他告诉我他得离开且很快就回来。
3. 由it 作形式宾语时, that 引导的宾语从句中的that 大多不可省略。
You can put it that it was arranged before.
您可以说这是以前安排好的。
(二)as if/as though, because, why 也可引导表语从句。
It looked as if it was going to rain.
看起来天好像要下雨。
That's because he didn't work hard enough.
那是因为他没有足够努力工作。
That was why I asked for three days' leave.
那就是为什么我请了三天假。
注意: because 引导表语从句时, 主句主语不能是 reason 或 cause, 而且 since 和 as 不能引导表语从句。