主语从句在复合句中作句子的主语。引导主语从句的词有从属连词that, whether, if；连接代词who, whoever, whom, what, whatever, whose, which；连接副词when, where, how, why等。《例句呈现》 观察下列例句，指出其中所包含的主语从句及引导词: 1. what is needed for a long trip is careful preparation. 该句中主语从句是______________，引导词为_____。 2. that jay zhou will come to my city excites everybody.
