Most of the time one or the other feels better, but every so often, "which" vs. "what" trips me up. So, what's the exact difference and when should you use one or the other?
Much of (what/which) scientists know about dinosaurs has been recently discovered. The phenomenon of (what/which) are known as corporate networks has also attracted attention. And yes, the ...
Which sentence would you use more, which is just simple wrong and why? This is the speech, that my father wrote. This is the speech, which my father wrote. This is the speech, what my father wrote. ...