在主语从句中,把It was … that去掉之后,就已经完全不像一个句子了。在强调句中,把It was … that去掉之后,还基本上像个句子。主语从句有以下的引导词:what, who, whom, whose, which, whatever, whoever, whichever强调句的引导词只有:that, who。