不能孤立的看how、what后跟什么词,这样会陷入僵化的思维状态,你要弄清楚的是what 或是how 到底要修饰什么?此处,what a hard life落脚点是在life,所以对life这个名字,当然要用what了.所以你要理解的话,就该先把句子还原,细细体会下面的用法,
A:people lived a hard life in the past.-->
what a hard life people lived in the past!
B:people's life is hard in the past.-->
how hard people's life is in the past!