what 和 which在做关系代词指代时有什么区别

what 和 which在做关系代词指代时有什么区别

要想分辨好这两者之间的关系，还真要费一下口舌。
1.做疑问代词时，无范围的选what,有范围的选which;
What would you like to eat for lunch?
Which do you like to eat for lunch, fish or meat?
2.定语从句中没有what;
3.名词性从句中，缺主语或宾语的用what。
I couldn't understand what you said just now.(what做从句宾语)

what引导主语关系从句，就是放在名词作主语的位子上。有一种情况要注意
Water is to fish what air is to human
which引导定语从句，特别是非限定性定语从句，就是在句中可用逗号comma分隔的。which前加介词可以替代where引导地点状语从句

。。。仿佛回到读书的时候。。···

What引导的从句相当于“一个名词+关系从句”：
What you need 你需要的东西
What I want to say 我想说的话
what I don't understand 我所不能理解的
在句中可作
主语：What she saw gave her a little fright. 她看到的情况使她有点惊恐。
宾语：I cannot do what you asked me to do. 我不能做你要求我做的事。
介词宾语：He was depressed by what he had gone through.他经历的事使他感到压抑。
表语：Times aren't what they were.
Which 只能代表东西或物，which前面可用介词，而what不行。
例如：The day on which I saw him was the greatest of my life.

关系代词that。关系代词that在从句中可作主语、宾语、表语。作宾语时，that可省略。它的先行词可以是指物的名词或代词，也可以是指人的名词或代词。例如：
(1)She told her mother all that had happened.她把所发生的事情都告诉了她的母亲。(先行词是all，that在从句中作主语)
(2)I”ll buy you the bike(that)you saw in the shop yesterday.我要给你买昨天你在商店里看到的那辆自行车。(先行词是the bike， that在从句中作宾语)
(3)The village is no longer the village that it was before.这个村子不再是从前的那个村子了。(先行词是the village，that在从句中作表语)
(4)He that wants to eat the fruit must climb the tree.想吃果子的就得爬树。(先行词是指人的代词he，that在从句中作主语)
3.关系代词which。关系代词 which在从句中作主语或宾语，其先行词是指物的名词或代词。例如：
(1)They first went to a large room which looked like a shop.他们首先到一个很大的看起来像个商店的房间去了。(先行词是指物的名词a large room， which在句中作主语)
(2)Have you got anything that you”d like to buy？你有想要买的东西吗？(先行词是指物的代词anything，which在从句中作宾语)
这就是具体的语法规则和例子 希望对楼主有所帮助