You can take any room that you like.

There is no clothes that fit you here.

7.当主句是以which开头的特殊问句时,定语从句关系代词一般用that而不用which.

Which of the books that had pictures was worth reading?

8.在强调句型" It is ... that ..." 中,只用that,不用which.

It is in this room that he was born twenty years ago.

9.在" such (the same) ... as ..." 句型中,关系代词要用as, 而不用which.

We need such materials as (not which) can bear high temperature.

10.表示" 正如... 那样 "," 正象..." 之意时, 用as, 不用which.

Mary was late again, as had been expected.

11.As 引导的定语从句可以放在主句前面, 也可以放在主句后面或主句中间,而由 which引导的定语从句只能放在主句后面。

As we all know, oceans cover more than 70% of the earth.

二、效果显著

定语从句能比较显著地彰显出写作者的实力。一个恰到好处的定语从句，能体现出作者对整体句子较为精确的掌控能力，并增强句子的紧凑感。

三、便于修正

由于定语从句并非语法难点，学生们在练习时也可进行 peer correction, 方便易行。

四、方便示范

在老师撰写的雅思高分范文中，很容易找到相应的定语从句范文例句，方便示范给学生，进行讨论和仿写。