定语从句which意思
定语从句which意思
which是定语从句的关系代词之一。GMAT语法考试限定，which有且仅有两种用法。
一，which前面有逗号，逗号前面是个名词，which就近指代那个名词。
(1) Tankfield emailed Pea some photos, which did not cheer Pea up.
which就近指代photos，定语从句中谓语动词did not cheer (Pea up)的发出者即从句主语即先行词photos，是photos没让豌豆家属高兴起来。
(2) Tankfield emailed Pea some photos, which Pea did not find interesting.
which就近指代photos，photos是定语从句中的宾语，把定语从句还原成一个完整句就是Pea did not find the photos interesting.
可以看到，上面两个句子都可以以that为关系代词改写，即
(1)’ Tankfield emailed Pea some photos that did not cheer Pea up.
(2)’ Tankfield emailed Pea some photos that Pea did not find interesting.
改写与原版区别在哪儿?就在一个逗号。which前面是名词，名词和which之间没逗号的，在GMAT语法里算错。
二，which前面是介词，介词前面是名词，which就近指代介词前的那个名词，名词和介词之间有无逗号均可。
Tankfield once lent Pea a book from which Pea glimpsed the basics of genes.
这个句子可以“拆”成如下两句：(每个定语从句都可以拆成两句，以先行词为拆分点)
Tankfield once lent Pea a book. Pea glimpsed the basics of genes from the book.
先行词实际上是定语从句中介词的宾语，这时，需要把介词提前，避免如下表达：
Tankfield once lent Pea a book, which Pea glimpsed the basics of genes from. (XXX)
Tankfield once lent Pea a book that Pea glimpsed the basics of genes from. (XXX)
以 下几种只能使用which的情况
1. 在“介词+关系代词”结构中，关系代词必须用which。
如： The house in which we live is very large. 我们住的房子非常大。
This is the reference book of which the teacher is speaking. 这就是老师正在谈及的那本参考书。
注意： 如果介词不放在修饰事物的限定性定语从句的句首， which就可换为that， 例如： This is the question which/that we've had so much discussion about. =This is the question about which we've had so much discussion. 这就是我们已经多次讨论过的`问题。
2. 先行词为“those+表事物的复数名词”时， 关系代词通常只用which而不用that。
如：you should grasp well those skills which may be used in the future work.
最后，记得这个特殊情况吧：当先行词是表示原因或方式的名词时，可以用that引导定语从句，相当于介词+which，that可以省略。
如： She likes the child for the very reason that (=for which) she loves his father. 她喜欢那个孩子因为她爱着孩子的父亲。
He didn't like the way that (=in which) she speaks to his mother. 他不喜欢她对他的母亲那样说话。
Imagine the speed that (=at which) he drives the car. 很难想象，他开车开得那么快。
The reason (that /for which /why) he came here was to ask for our help.他来这里的原因是寻求我们的帮助。
高中英语定语从句学习方法
方法1、要注意关系代词的选用。首先记住几个大原则，譬如whothat引导人的从句，thatwhich引导物的从句whose表示所属关系。其次还要注意在某些场合下关系代词的固定使用，譬如先行词中有人有物要用that，这些情况等等。值得一提的是，what无论如何不能引导定语从句。
方法2、要注意从句中动词的类别。这主要是说看看这个动词是及物还是不及物。在不及物动词的情况下，要记住带上固有的介词。还要注意这个介词放置的位置，可以提前到关系代词前，也可以紧跟在动词之后。这种情况是考试最爱考的，其中涉及到动词与介词的固定搭配，句子理解与分析，是热点难点。
方法3、在熟练掌握定语从句的情况时，要注意省略关系代词和使用分词结构来代替从句。
