The question remains whether they will be able to help us. 问题还是他们能否帮我们。
At that time，it seemed as if I couldn't think of the right word. 当时，我似乎怎么也想不出一个恰当的字眼来。 引导表语从句的关联词的种类： (1）从属连词that
e.g The trouble is that I have lost his address. 麻烦是我把他的地址丢了。
that是连词,没有词义，在句中不作成分，因此一般不可省略(但在口语中有时that可省略)。
(2) 从属连词whether，as，as if / though引导的表语从句。
如：He looked just as he had looked ten years before.他看起来还与十年前一样。 It sounds as if someone is knocking at the door.听起来好像有人在敲门。
(3) because，why引导的表语从句。
如：That's because he didn't understand me.那是因为他没有理解我（That's because…强调原因） That's why he got angry with me.那正是他对我生气的原因。（That's why…强调结果） 注意：表示结果或名词reason作主语时，后面的表语从句表示原因时要用that引导，不宜用because.
如：The reason why I was sad was that he didn't understand me.我难过的原因是他没有理解我。
(4) 连接代词who，whom，whose，what，which，whoever，whatever，whichever 连接副词 where，when，how，why
e.g The problem is who we can get to replace her. 问题是我们能找到谁去替换她呢。 The question is how he did it. 问题是他是如何做此事的。
That was what she did this morning on reaching the attic. 那就是她今晨上了阁楼干的。
(5) 使用虚拟语气的表语从句
在表示建议、劝告、命令含义的名词后的表语从句，谓语动词需用“should+动词原形” 表示，should可省略。常见的词有：advice，suggestion，order，proposal，plan，idea等。 e.g My suggestion is that we （should） start early tomorrow. 我的建议是我们明天一早就出发。
4. 同位语从句
英语中有一些名词如fact, idea, news, word, hope, promise, suggestion, reply, problem, belief, doubt, truth, order, thought等，它们本身有一定的意义，但表达得不够具体。为了使其表达的意义更加具体明确，其后常跟有一个从句，用来补充说明该名词的内容，这个从句就叫做同
第 6 页 共 6 页
位语从句。
(1) 同位语从句的引导词
①表示陈述意义时通常用that。注意that不能省略。
同位语从句说明的名词常见的有：ability, advice, answer, belief, doubt, discovery, fact, fear, hope, idea, information, message, news, order, possibility, problem, proposal, question, story, suggestion, theory, thought, word(消息)等,同位语从句一般都是用来解释说明一些抽象名词，而不可说明的名词是不会接同位语从句的。比如：man, water, sun等具体的人或事物。 e.g There is no doubt that the prices of cars will go down.
The belief that the company will make a great is shared by everyone.
②表示“是否”的意思时只能用whether，不能用if。这一点与主语从句相似。 e.g The question whether he can finish the work within two days remains unknown. ③表示疑问时也可用其他引导词where, when, why, how, who, what来引导。 e.g This student asked a good question why pollution can’t be stopped. I have no idea where I should go.
I have no idea how I can get to the railway station.
(2) 同位语从句和定语从句的区别
① 定语从句相当于一个形容词, 它对先行词起修饰、描述和限制的作用。同位语从句相当于名词，属于名词性从句，它是对前面名词内容的具体表述，它们之间的关系是同位关系。试比较：
The news that you heard is not true. 你听到的那个消息不是真的。（定语从句）
The news that he has died is true. 他已经去世的消息是真的。（同位语从句，说明了 news 的具体内容，即he has died）
② 同位语从句常跟在 news, fact, promise, idea, word, message, hope, truth, answer, proposal, suggestion, order, information 等少数名词之后，而一般名词之后都可跟定语从句。 e.g He didn’t give the answer why he was late. 他没回答他为什么迟到这个问题。（同位语从句）
Then rose a question where we should go. 于是产生了一个问题：我们该到哪里去？（同位语从句）
③ that 在定语从句中充当某一成分, 是关系代词; that 在同位语从句中不作任何成分，仅把主句与从句连接在一起，是从属连词。如：
The fact that just now you talked about interests me. 你们刚才谈论的事情使我感兴趣。（定语从句）
The fact that he failed in the exam made his parents very angry. 他考试没及格这个事实使他的父母很生气。（同位语从句）
④ when, where, why, how, who, whom, which 如果引导定语从句, 它们分别指前面先行词所
第 7 页 共 7 页
表示的时间、地点、原因、方式、人和物，否则引导的就是同位语从句。试比较： I still remember the day when he was killed. 我还记得他被害的那一天。(定语从句) I have no idea when he was killed. 我不知道他什么时候被害的。（同位语从句） They didn't go to the town where they were born.他们没有去他们出生的小镇。(定语从句) They didn't answer the question where they were born.他们没有回答他们在哪里出生这个问题。（同位语从句）
⑤ whether, what 可引导同位语从句，但通常不可引导定语从句。
e.g We have no information whether he is alive. 我们不知道他是否活着。（同位语从句）
Next comes the question what step we should take. 接着的问题是我们下一步该做什么。（同 位语从句）
二．定语从句
定语从句（Attributive Clauses）在句中做定语，修饰一个名词或代词，被修饰的名词,词组或代词即先行词。定语从句通常出现在先行词之后，由关系词（关系代词或关系副词）引出。 关系代词有：who, whom, whose, that, which等。 关系副词有：when, where, why等。 1. 关系代词引导的定语从句
关系代词所代替的先行词是人或物的名词或代词，并在句中充当主语、宾语、定语等成分。关系代词在定语从句中作主语时，从句谓语动词的人称和数要和先行词保持一致。 1）who, whom, that 这些词代替的先行词是人的名词或代词，在从句中所起作用如下： e.g Is he the man who/that wants to see you?他就是你想见的人吗？（who/that在从句中作主语） He is the man whom/ that I saw yesterday.他就是我昨天见的那个人。（whom/that在从句中作宾语）
2) Whose 用来指人或物，(只用作定语, 若指物，它还可以同of which互换）。
e.g They rushed over to help the man whose car had broken down.那人车坏了，大家都跑过去帮忙。
Please pass me the book whose (of which) cover is green. 请递给我那本绿皮的书。 3）which, that 它们所代替的先行词是事物的名词或代词，在从句中可作主语、宾语等，例如：A prosperity which / that had never been seen before appears in the countryside. 农村出现了前所未有的繁荣。（which / that在句中作宾语）
The package (which / that) you are carrying is about to come unwrapped. 你拿的包快散了。(which / that在句中作宾语）
2. 关系副词引导的定语从句
关系副词可代替的先行词是时间、地点或理由的名词，在从句中作状语。
第 8 页 共 8 页
1）when, where, why 关系副词when, where, why的含义相当于\介词+ which\结构，因此常常和\介词+ which\结构交替使用.
e.g There are occasions when (on which) one must yield. 任何人都有不得不屈服的时候。 Beijing is the place where (in which) I was born. 北京是我的出生地。
Is this the reason why (for which) he refused our offer? 这就是他拒绝我们帮助他的理由吗？
2）that代替关系副词
that可以用于表示时间、地点、方式、理由的名词后取代when, where, why和\介词+ which\引导的定语从句，在口语中that常被省略.
e.g His father died the year (that / when / in which) he was born. 他父亲在他出生那年逝世了。 He is unlikely to find the place (that / where / in which) he lived forty years ago. 他不大可能找到他四十年前居住过的地方。
3. 判断关系代词与关系副词
方法一： 用关系代词，还是关系副词完全取决于从句中的谓语动词。及物动词后面无宾语，就必须要求用关系代词；而不及物动词则要求用关系副词。例如： This is the mountain village where I stayed last year. I'll never forget the days when I worked together with you.
判断改错（注：先显示题，再显示答案，横线；用不同的颜色表示出。） （错） This is the mountain village where I visited last year. （错） I will never forget the days when I spent in the countryside. （对） This is the mountain village (which) I visited last year. （对） I'll never forget the days (which) I spent in the countryside.
习惯上总把表地点或时间的名词与关系副词 where, when联系在一起。此两题错在关系词的误用上。
方法二： 准确判断先行词在定语从句中的成分(主、谓、宾、定、状)，也能正确选择出关系代词/关系副词。
例1. Is this museum ___ you visited a few days ago? A. where B. that C. on which D. the one 例2. Is this the museum ____ the exhibition was held？ A. where B. that C. on which D. the one 答案：例1 D，例2 A
例1变为肯定句： This museum is ___ you visited a few days ago. 例2变为肯定句： This is the museum ___ the exhibition was held.
在句1中，所缺部分为宾语，而where, that, on which都不能起到宾语的作用，只有the one既做了主句的表语，又可做从句的宾语，可以省略关系代词，所以应选D。
第 9 页 共 9 页
而句2中, 主、谓、宾俱全，从句部分为句子的状语表地点，既可用副词where，又因 in the museum词组，可用介词in + which 引导地点状语。而此题中，介词on 用的不对，所以选A。
关系词的选择依据在从句中所做的成分，先行词在从句中做主、定、宾语时，选择关系代词 (who, whom, that, which, whose)； 先行词在从句中做状语时，应选择关系副词 ( where 地点状语，when 时间状语，why 原因状语) 。
4. 限制性和非限制性定语从句
1) 定语从句有限制性和非限制性两种。限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确；非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开。
e.g This is the house which we bought last month.这是我们上个月买的那幢房子。（限制性） The house, which we bought last month, is very nice.这幢房子很漂亮，是我们上个月买 （非限制性）
2) 非限定性定语从句不能用that引导, 一般用引导词which / as或who（指人），非限定性定语从句既可以修饰主句的部分内容，也可修饰主句的全部内容。as引导的非限定性定语从句既可以放在主句之前，也可以放在主句之后，但which或who引导的非限定性定语从句不能放在主句句首。
e.g As we all know, the moon is a satellite of the earth.
The large area is covered with thick snow, which affects people's life greatly. His speech, which bored us to death, was over at last. Her sister, who lived in another city, was coming to visit her.
5. as, which 非限定性定语从句
由as, which 引导的非限定性定语从句，as和which可代整个主句，相当于and this或and that。as一般放在句首，也可以放在句中，which在句中。 e.g As we know, smoking is harmful to one's health.
The sun heats the earth, which is very important to us. 典型例题
1）Alice received an invitation from her boss, ___came as a surprise. A. it B. that C. which D. he
答案C. 此为非限定性从句，不能用 that修饰，而用which.，it 和he 都使后句成为句子，两个独立的句子不能单以逗号连接。况且选he句意不通。
2）The weather turned out to be very good, ___ was more than we could expect. A. what B. which C. that D. it
答案B。which可代替句子，用于非限定性定语从句，而what不可。That 不能用于非
第 10 页 共 10 页