由what 引导的从句

* I think Father would like to know what I've been up to so far, so I decided to send him a quick note. 我想父亲想知道目前我在做什么，所以我决定给他发个短信。
* Our hometown has changed a lot, and now it is quite different from what it used to be a few years ago. 我们的家乡变化很大，它现在与数年前的样子完全不同。
* A modern city has been set up in what was a wasteland ten years ago. 一座现代化城市已经在十年前是垃圾场的地方拨地而起。