whom|爲什麼在表語從句中不能作主語

whom 不管在什麼從句裏都不能作主語，只能作賓語。能作主語的是who，而且who也能作賓語。

whom可用於表語從句，主語從句，賓語從句和定語從句。例句如下：

1、Whom you will trust is always your parents.(主語從句)

2、The question is whom you can turn to for help when in trouble.(表語從句)

3、We don't know whom the manager will choose to be his assitant.(賓語從句)

4、The teacher introduced a star to us whom the teenagers like most.(定語從句)

這些句子中的whom都可以換成who，並且定語從句中的還可以省略。