连词种类 连词 备注 从属连词 that 无意义，不作成分，不可省略 whether "是否"，不作成分，不能用if代替 连接代词 what, who, whom, whose, which 有词义，可作主语、宾语、表语、定语 连接副词 where, when, why, how 有词义，作状语 　　

　　I'm not sure about the question whether he will come.

　　对于他来不来这个问题，我不太确定。

　　They were worried over the fact that you were sick.

　　他们为你生病发愁。

　　I have no idea when he will come back.

　　我不知道他什么时候回来。

　　The question who should go abroad required consideration.

　　谁会出国这个问题还需要考虑。

　　She had no idea why she thought of him suddenly.

　　她不明白她为什么突然想到了他。

　　[即时演练1]　用适当的连接词填空

　　①(2017·天津高考改编)There is no doubt that I will enhance its reputation through my efforts.

　　②We'll discuss the problem whether the sports meeting will be held on time.

　　③The fact that she works hard is well known to us all.

　　④I have no idea when he will start.

　　⑤Do you have any idea what it means to be poor?

　　三、同位语从句的注意事项

　　1．分隔式同位语从句：有时同位语从句与其所说明的名词会被其他成分隔开，从而形成分隔式同位语从句，这样做主要是为了保持句子结构平衡，避免头重脚轻。

　　Word came that some wolves were caught around that village.

　　有消息传来说在那个村子周围捕获了几只狼。

　　2．名词suggestion, order, demand, command, request, desire, proposal等后的同位语从句要使用虚拟语气，即从句谓语用"should＋动词原形"，should可以省略。

　　The suggestion that the new rule (should) be adopted came from the chairman.

采纳新规则的建议是主席提出的。