that在从句中作主语或宾语，既可以指人又可以指物；which在从句中作主语或是宾语，只能指物
、that与which的区分
1。 指物时宜用 that 的情况：
>①、 当先行词为 all, none, much, little, few, something, anything, everything, nothing 等不定代词时。
All that can be done has been done。
>②、当先行词既指人又指物时。 He spoke of the men and the thing (that) he had seen abroad。
>③、当先行词是疑问词 who, what, which 时或者句子以疑问词 who , what , which 打头时。
Who that has such a home doesn’t love it?
>④、先行词是序数词、形容词最高级 或者 当先行词被序数词或形容词的最高级修饰时。
This is one of the best films that I have ever seen。
This is the best that can be done now。
>⑤、 当先行词被 the very, the only, the last, the same , just, one of , any, every , few , little , no , all , one of 等修饰时。
This is one of the very book that I am looking for。
>⑥、关系代词在从句中作表语。 Mary is no longer the girl that she used to be。
2。 只能用 which 不能用 that 的情况。
>①、 引导非限定性定语从句修饰某物或整个句子。
Bruce went towards the fire, which was still smoking。
Tom came back late, which made his parents very angry。
>② 、关系代词作介词的宾语。This is the house in which Lu Xun once lived。
>③、 that，those作主语时Those which are on the desk are English books。
④。先行词是专有名词、整个句子或世界上独一无二的物质名词时，一般用非限定性定语从句修饰。
The sun, which gives us light and heat, is very big。
注意 当引导定语从句的关系代词在从句中作主语时，那么定语从句中的谓语动词的数的形式应与先行词保持一致。
问：定语从句在什么情况下我们用定语从句，定语从句的结构又是怎么样的
答：定语从句是由关系代词和关系副词引导的从句，其作用是作定语修饰主句的某个成分，定语从句分为限定性和非限定性从句两种。状语从句分为时间状语从句，结果状语从句，让步状...详情>>
答：先行词是定语从句的引导词前面的被定语从句所修饰的名词、代词.在定语从句中充当一定的成分. 我们可以这样认为, 之所以称它为先行词, 是因为修饰它的定语从句总是放...详情>>
