連詞代詞what, who, which, whose等引導(dǎo)的主語從句。
這些連接代詞作用相當(dāng)于代詞，在從句中擔(dān)當(dāng)主語、賓語、表語、定語等。
?What we need is more time.
?Who was responsible for the accident is not yet clear.
?Whose book it is not important.
?Which school you want to go matters much.
連接副詞when, where, why, how引導(dǎo)的主語從句。
?這些連接副詞相當(dāng)于副詞，在從句中充當(dāng)狀語。
?Why he did this is not known.
?When he will come is still unknown.
? It is not known why he did this.
? How he succeeded is unknown to us.
? Where we should hold the meeting needs to be discussed.
注意 wh-引導(dǎo)的主語從句也常用it作形式主語。
也可用whatever,whoever,whomever,whenever,wherever等詞引導(dǎo)主語從句，表示“無論什么”、“無論誰”、“無論何時”、“無論在（到）哪里”等。
? Whoever told you to give up smoking was quite right.
? Whatever he gave you should be handed in.
? Whoever told you that was lying.
? Whoever comes is welcome.