3.由wh-引导的表语从句

What is perhaps the most valuable is what you learn about yourself and your own culture．(人教大纲版高三第71页)(引导表语从句的what在从句中作learn的宾语)

也许最有价值的是你对你自己和自己的文化有了更多的了解。

A nest is to a bird what a house is to a man．(人教大纲版高二上第21页)

鸟巢对于鸟的作用，就像房屋对于人的作用。

提示：

此句中的what在表语从句中作表语。属于这样一个句型“A is to B what C is to D”，为隐喻结构，意为“A对B而言正如C对D一样”。

The people is to the people's army what water is to fish．

人民军队离不开人民，就像鱼离不开水一样。

Arms are to the body what branches to a tree．(人教大纲版高二上第21页)

胳膊对于身体就像树枝对于树木一样。

Even though the pure water is what gives sea water its main properties，the salinity of sea water affects both its weight and freezing point．(人教大纲版高二下第20页)(what在从句中作主语)

虽然是纯水赋予了海水的主要特性，然而海水的盐度却影响了它的重量和冰点。

The problem is who we can get to replace her．

问题是我们能找到谁去替换她呢。

Many countries have set up program mes to encourage and develop young footballers，and this is where the clubs go to assess athletes and find stars of the future．(人教大纲版高三第139页)

许多国家安排了计划来鼓励和促进那些年轻足球队员的发展。这就是俱乐部要去评价运动员和发现未来球星的地方。

I now feel as if that was when my life really began．(人教大纲版高二上第55页)

现在我觉得那天是我一生真正的开始。

This is how American jeans were introduced to the world．(人教大纲版高三第134页)

就这样，美国牛仔裤在世界上风行了起来。

That's why I now look so old．(人教大纲版高一下第18页)

这就是我现在看上去这么苍老的缘故。