6．When shall we use the relative pronoun“who”and“whom”?

　　7．这两句中的定语从句都是由 whose 引导的, 在从句中 whose 只能作定语。

　　A 句中 whose 修饰人。

　　B 句中 whose 修饰物, 这个句子相当于：Look at the house the roof of which is red. 或：Look at the house with a red roof.

　　8．这三个句子中, 所含的定语从句都是由关系副词引导的。

　　A．where 引导的定语从句修饰一个表地点的名词, where 本身作从句中谓语的地点状语, 这时, where 可由介词 to + which 来替代。

　　B．when 引导定语从句修饰一个表示时间的名词, when 在从句中作时间状语, when 可用介词 on＋which 来替代。

　　C．why 引导定语从句修饰一个表示原因的名词, why 在从句中作原因状语。why 可用介词 for + which 来替代。

　　从以上三个句子来看, 关系副词引导定语从句, 一般情况下, 都可用“介词+关系代词”来替换关系副词。

　　9．不一定。如果表地点或表时间的名词在定语从句中作主语或宾语, 就不能用关系副词引导宾语从句, 而应由相应的关系代词引导。如：

　　A．Mike is studying in a school that/which was built in 1928．

　　B．Those days that / which we spent with Mary were wonderful.

　　10．

　　A．As is known to all, the compass was first made in China.

　　B．This is the same pen as I lost yesterday.

　　C．They have produced as much iron this year as they did last year.

　　D．We ought to make friends with such people as kind and hard working.