3.由wh-引导的同位语从句

连接代词who，which，what和连接副词where，when，why，how亦可引导同位语从句。

They had no idea what they were up against．(人教大纲版高三第17页)

他们对将要面临的情况毫无所知。

In later years the question arose who was the first to reach the top．(人教大纲版高三第17页)

在随后的岁月里，问题就产生了:谁是第一个登上顶峰的?

We haven't yet settled the question wherewe are going to spend our summer vacation．

到哪儿去度暑假，这个问题我们还没有决定。

One of the main themes of the summit was“sustainable development”，or the

question how we can continue developing the world without damaging the environment．(人教大纲版高二上第67页)

其主题之一是“可持续发展”，也就是如何在不破坏环境的情况下使世界继续发展的问题。