一、主语从句(subject clause)
1. 在复合句中充当主语的从句称之为主语从句, 一般置于句首。
主语从句引导词有:
(1)连词that和whether, 在主语从句中只起连接作用, 不充当任何成分。
(2)连接代词who, whoever, whom, whose, what, whatever, which, whichever, 在主语从句中充当主语、宾语、表语。
(3)连接副词when, where, how, why, 在主语从句中作状语。
*That he worked out the complex problem astonished other students. 
他解决了这个复杂的题目让其他同学感到惊讶。
*When the exam of qualification will be held hasn’t been decided. 
资格考试什么时候举行还没决定。
*Whether he will participate in this campus art festival isn’t clear.
他是否参加这次校园艺术节还不清楚。
*What worried the old couple was that their children got involved in the crime.
令这对老夫妇担忧的是他们的孩子参与了这次犯罪。
*Whatever happens you may be quite sure that I will not blame you.
不管发生什么事, 你可以确信我不会责备你。
