一、定语从句概念:定语从句(attributive clause),顾名思义,就是一个句子作定语从属于主句。定语一般是由形容词充当,所以定语从句又称作形容词从句。另外,定语从句是由关系代词或关系副词引导的,故又称作关系从句。定语从句一般放在它所修饰的名词或代词之后,这种名词或代词被称作先行词。请看例:The woman who lives next door is a teacher.先行词 woman,who为引导词。常见的关系代词有:who, that, which,whom,whose,。
(一)关系代词who, whom和 whose的用法:who代替人,是主格,在定语从句中作主语。例如:A teacher is a person who teaches students.教师是教学生的人。I will never forget the teacher who taught us chemistry in the first year of my senior middle school. 我将永远不会忘记在高一时教我们化学的那位老师。whom代替人,是宾格,在定语从句作宾语,在非正式英语常可省略。例如:Do you know the gentleman whom we met in the school library yesterday? 昨天我们在学校图书馆里遇到的那位先生你认识吗?This is the student whom my father taught ten years ago. 这是我爸爸十年前教的学生。The girl who I saw is called Mary. 我见到的那个女孩名叫玛丽。(在非正式英语中,主格who代替了宾格whom,亦可省略)whose一般代替人,有时亦可代替物,是所有格,在定语从句作定语。例如:The girl student whose father is a senior engineer used to study abroad. 其父是一位高级工程师的那个女学生过去在国外留学。Do you know the name of the hotel whose window we can see here? 我们这儿能看到窗户的那个宾馆叫什么名字,你知道吗?(关系代词whose指代先行词hotel,正式用法应该用of which。whose window=the window of which,意思是:the window of the hotel。)
(二)关系代词which的用法:which代替物,在定语从句作主语或宾语,作宾语时还可省略。例如:I do not like stories which have unhappy endings.我不喜欢有不幸结局的小说。(which可以换成that)Tom works for a factory which makes watches.汤姆在一个制表厂工作。(which可以换成that)。
(三)关系代词that的用法:that既可指人又可指物,在当代英语中大多指物,在定语从句作主语或宾语,作宾语时还可省略。例如:Is she the girl that sells newspapers?她是卖报纸的那个女孩吗?(that可以换成who)Where is the ice-cream that was in the fridge?放在冰箱的冰激凌哪儿去了?(that可以换成which)Is this the book that you want to buy?这是你要买的那本书吗? (that可以换成which,在定语从句作宾语,还可以省略)
二、关系副词引导的定语从句常用的关系副词只有三个:when, where, why,在定语从句中充当时间、地点和原因状语。它们的用法大家不妨记住一个口诀:the time when the place where the reason why
(一)关系副词when的用法:关系副词when代替的先行词表示的是时间,when在定语从句作时间状语。例如:In Beijing July and August are the months when it rains very often.北京的七月和八月是常下雨的月份。(when先行词是months)Do you remember the day when we first went to the Summer Palace?你还记得我们第一次去颐和园的那一天吗?(when先行词是day, 当代英语里when可以用that替代,这时关系代词that就变成了表示时间的关系副词)I haven’t seen her since the year when I left Tokyo.自从我离开东京的那一年我就一直没见到过她。(when先行词是year,同样when可以用that代替)
(二)关系副词where的用法关系:副词where代替的先行词表示的是地点,where在定语从句作地点状语。例如:During the Spring Festival I went back to the town where I was brought up.春节期间,我回到了生我养我的家乡。(where的先行词是town)This is the place where Li Bai once lived.这是李白曾经生活过的地方。(where先行词是place)上面这个句子不可以将where改为that,因为that不能作为表示地点的关系副词。试比较下句:This is the place that Li Bai once visited.这是李白曾经游览过的地方。(that的先行词同样是place,但这个that是关系代词,在定语从句中作宾语,可以省略,还可以用which替换)注:与不及物动词连用的用关系副词,与及物动词连用的用关系代词。如以上的that 和where.
(三)关系副词why的用法关系副词why代替的先行词表示的是原因,why在定语从句作原因状语。例如:The reason why I am phoning you is to ask you whether you have got my email.我打电话给你的原因是想问问你是否收到了我的电子邮件。(why先行词是reason, 当代英语里why可以用that替代,这时关系代词that就变成了表示原因的关系副词,还可以将why省略)This is the reason why he came late to school.这就是他为什么上学迟到的原因。(why先行词是reason,why可以用that替代,还可以省略)
三,关系代词who与that的区别1. 当关系代词用作主语时,多用主格who。例如:He who loses hope loses all.失去希望的人就失去一切。(先行词为代词he, they, any, all, one等时,多用who)I met Alice, who told me that she was learning Chinese.我遇见艾丽斯,她告诉我她在学汉语。(在非限制性定语从句中,用who)2. 当关系代词用作介词后的宾语时,用宾格whom,不用that。例如:The man to whom our headmaster talked just now is our English teacher.我们校长刚才与他谈话的那个人是我们的英语老师。(介词与关系代词紧密相连时,只能用宾格whom,不可用主格who)注意:介词与关系代词不是紧密相连时,或者说介词放在句子后面时,这时可以用主格who,也可用that,还可以省略关系代词。因此,上面的这句话还可以有如下四种说法:(1) The man whom our headmaster talked to just now is our English teacher.(2) The man who our headmaster talked to just now is our English teacher.(3) The man that our headmaster talked to just now is our English teacher.(4) The man our headmaster talked to just now is our English teacher.第4句简洁、自然,所以口语中用得最多。3. 当关系代词泛指人时,多用that。例如:He is a man that is never afraid of failure.他是个从不怕失败的人。(that用来泛指人)4. 当关系代词出现在who开头的疑问句时,应用that。例如:Who is the girl that is talking to Tom in English?用英语同汤姆交谈的那个女孩是谁?(避免重复使用who,以免造成误解或语义含混不清)
四,关系代词which与that的区别1. 当先行词为all, much, little以及不定代词anything, something, everything等时,关系代词多用that。例如:All that glitters is not gold. 闪闪发光物,未必尽黄金。She told me everything that she knew. 她把她所知道的一切都告诉了我。2. 当先行词的前面有形容词最高级、序数词或限定词the only, the very, all, every, any, no等时,关系代词一般都用that。例如:This is the best novel that I have ever read. 这是我读过的最好的一部小说。He is the only person that has been invited to the ball. 他是惟一应邀参加舞会的人。3. 当关系代词出现在which开头的疑问句时,应用that。例如:Which was the hotel that was recommended to the foreign guest? 哪一个是推荐给外宾的宾馆?(这里使用that很明显是为了避免重复which)4. 在非限制性定语从句中,关系代词一般只用which。例如:Beijing, which is the capital of the People’s Republic of China, will host the 2008 Olympic Games. 北京是中华人民共和国的首都,将主办2008年奥运会。5. 介词后的关系代词用which,而不用that。例如:She has collected 600 stamps, 60% of which are German stamps. 她收集了600张邮票,其中60%是德国邮票。
五、限制性定语从句和非制性定语从句:限制性定语从句中,从句与其所修饰的先行词之间关系很密切,若缺少,句意则不完整,故从句前不用逗号隔开;非限制性定语从句中,从句与其所修饰的先行词之间关系不太密切,若缺少,句意则仍完整,故从句前一般都用逗号隔开。试比较以下两组句子:The water which has been polluted by the factory is not fit to drink.被工厂污染的水不宜饮用。(如果缺少定语从句,句子的主要意思会受到影响)Water, which is a clear liquid, is widely used in our everyday life.水是一种清澈的液体,在我们的日常生活中应用非常广泛。(如果缺少定语从句,句子的主要意思不会受到影响)His brother who is nineteen years old is serving in the army now.他的一个十九岁的哥哥现在部队服役。(表明他不只一个哥哥)His brother, who is nineteen years old, is serving in the army now.他的哥哥,今年十九岁,现在部队服役。(表明他只有一个哥哥)
六、定语从句的位置如前所述,定语从句一般总是直接置于所修饰的名词或代词之后。有时候,定语从句与先行词之间插入了其他的短语,这样它们被分隔了,这种情况下的定语从句被称作隔离定语从句。
七、定语从句与同位语从句的区别:同位语从句与定语从句从形式上看好像没什么区别,实际上从含义和功能上看,还是比较易区分的。同位语从句的先行词一般为fact, idea, news, thought, reply, report, problem等抽象名词,而且关联词大都为that,在idea, problem等词后根据句意可能用到who, when, why, how等其他关联词。关联词that在同位语从句中仅仅起连接作用,不作任何成分,但又不可省略。定语从句的关联词(关系代词和关系副词)在从句中是要充当句子成分的且有实际含义。试比较以下两句:The suggestion that we should practise speaking English every day came from our monitor.我们每天都应练习说英语的建议是我们的班长提出来的。(同位语从句)The suggestion that our monitor put forward at the meeting is very valuable.我们的班长在会上提出的建议很有价值。(定语从句)