定语从句21大核心考点（十二）定语从句(Attributive Clauses)定语从句（Attributive Clauses）定义：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(antecedent)。
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。
关系词分类：由在从句中的地位划分上讲,引导词可分为三类:一．主语,宾语引导词．如: who , whom , that , which , as二 .定语引导词．如: whose三 .状语引导词．如: where , when , why（非常六加三，九个关系词）关系词的作用：一是引导从句;作为从句的重要标志.二是代替先行词, 被定语从句修饰的词称为先行词,先行词一般是名词和不定代词，如:some-, any-, every-和no与-boy,-thing的合成词；或all、none、any、some、that、those等代词。
数词也可以作先行词，人称代词也同样可作先行词; 三是在从句中充当成分,可充当主语、表语、宾语、定语、状语等。
关系词在从句子中充当了成分，其意思就是先行词的意义，所以在从句中不能重复其意。
解题技巧：牢记口诀：“一看是人还是物，二看介词在何处，三看句中作何用，四看是否属特殊”一、关系代词引导的定语从句【考点1】关系代词who & whom【考点2】关系代词whose （口诀：定从之中少定语，whose为你唱一曲；whose指人又指物，所属关系要记住。
）【考点3】关系代词that 的用法【考点4】关系代词which【考点5】关系代词（that, which, whom）的省略（The omission of the relative pronouns）:【考点6】as 的用法二、关系副词引导的定语从句【考点7】关系副词where【考点8】where一词引导的定语从句与状语从句。
【考点9】关系副词when【考点10】关系副词why三、判断关系代词与关系副词【考点11】关系代词与关系副词区别四、限制性和非限制性定语从句【考点12】非限制性定语从句Non-restrictive【考点13】as, which 非限定性定语从句五、介词+关系词（重点难点）【超级考点14】Prep.（介词）+ which/whom【考点15】介词+关系代词的结构拓展---Prep. + which/whom +to do…【考点16】名词(代词)+ of which/whom ( most of /both of/some of/ …+ which/whom)六、特例（Special ones）：【考点17】分隔性定语从句(带有插入语的定语从句)。
【考点18】特殊关系代词than & but七、定语从句与名词性从句的区别（先行词和关系词二合一）【考点19】whoever = anyone who 或those who【考点20】what/whatever; that/what; who/whoever八、定语从句的主谓一致【考点21】定语从句的主谓一致九、定语从句与六种易混句型巧区分十、【相似结构对比练】十一、【综合精炼】单项填空十二、定语从句改错40题十三、巧联定语从句十四、定语从句十大典型错误例析四、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，例如：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，是我们上个月买的。
（非限制性）2) 当先行词是专有名词或物主代词和指示代词所修饰时，其后的定语从句通常是非限制性的，例如：Charles Smith, who was my former teacher, retired last year. 查理·史密斯去年退休了，他曾经是我的老师。
My house, which I bought last year, has got a lovely garden.我去年买的的那幢房子带着个漂亮的花园。
This novel, which I have read three times, is very touching. 这本小说很动人，我已经读了三遍。
3) 非限制性定语从句还能将整个主句作为先行词, 对其进行修饰, 这时从句谓语动词要用第三人称单数，例如：He seems not to have grasped what I meant, which greatly upsets me. 他似乎没抓住我的意思，这使我心烦。
Liquid water changes to vapor, which is called evaporation. 液态水变为蒸汽，这就叫做蒸发。
【说明】：1、关系代词that和关系副词why不能引导非限制性定语从句。
2、在非限制性定语从句关系代词不能省略。
【经典对比】：1. She has a son who is a doctor.她有一个当医生的儿子。
（不止一个）She has a son，who is a doctor.她有一个儿子，是当医生的。
（仅有一个）2.He said nothing that made her angry.他没说使她生气的话。
He said nothing，which made her angry.他没吭声，她非常生气。
= He said nothing and that made her angry.【考点12】非限制性定语从句Non-restrictive【考例】1.You can find whatever you need at the shopping centre, ___ is always busy at the weekend.(上海卷06春-37)A. thatB. whereC. whatD. which2.John said that he'd been working in the office for an hour,___ was true.(上海卷2000春)A. heB. thisC. whichD. who3.The weather turned out to be very cold, ____ was more than we could expected.(94)A. whatB. whichC. thatD. it4.In the office I never seem to have time until after 5:30 p．m．, ＿＿＿＿many people have gone home．(上海’95)A．whose time B．that C．on which D．by which time5.Wilma became the first American woman to win 3 Olypic gold medals in track, ___ made her mother very proud. (91上海)A. itB. thatC. whichD. this6. He was very rude to the customs officer, ____ of course made things even worse. (98上海)A. whoB. whomC. whatD. which7.(天津卷04-23）Helen was much kinder to her youngest son than to the others , ___ , of course , made the others envy him .A. whoB. thatC. whatD. which8.（07湖南卷）32．By serving others, a person focuses on someone other than himself or herself, ___________ can be very eye-opening and rewarding. A．who B．which C．what D．that【答案与简析】1-5 DCBDC 6 DDB3.先行词5:30 p．m．与time之间是一种同位关系，可用which来作定语替代。
从句中的完成状态，常与by短语连用，故选D。
【超链接】I.1.that不能用来引导非限制性定语从句2.除which外，还可用when where whose whom等引导非限制性定语从句，且各自的用法及差异与它们用在限制性定语从句时相同。
如：Next month, when you’ll spend your summer holidays in your hometown, is approaching．下个月即将来临，届时你们将在家乡度暑假。
（关系副词when指代表示时间的名词next month，并作从句的状语。
）She is going to live in Macao, where she has some close friends．（关系副词where指代表示地点的名词Macao，她要到澳门去居住，在那里她有几个密友。
并在从句中作状语。
）3.在非限制性定语从句中作宾语的关系代词不能省略。
如：He was eager to go to the hospital to see his stepmother, whom he loved as his own mother．他迫切地想到医院去看望他继母，他把继母当自己的亲妈妈一样爱戴。
4.非限制性定语从句的关系代词which，既可以指代前面的先行词，也可以指代前面整句的含义。
5.修饰先行主句时as和which的差异从句置于句首时，非限制性定语从句只能用as引导，而置于句末时，as和which都行。
II.非限制性定语从句的五个“不能”一、非限制性定语从句通常不能用that引导。
如：1. I like the book, which was bought yesterday. 我喜欢这本书，这是昨天买的。
2. I like the book which / that was bought yesterday. 我喜欢昨天买的那本书。