In Mandarin Chinese, You Can't Use Say as a Subject.

Mandarin also expresses the sort of the everyone everything by putting the question word and then modifying the verb with dau, meaning all. In object position in Mandarin, normally you use just a straight up question word. What's interesting is it appears to be across all sorts of languages is that using a bare question word as an indefinite is restricted to certain circumstances that license that behavior. We do not have time on this show to cover all of them.