我完全不知道你在说什么。

I do ___not ___have ___the ___faintest ___idea what you are talking about.

我完全不知道是谁给了我那些杯子。

I do ___not ___have ___the ___faintest ___idea who gave me those mugs.

她完全不知道如何解决这个复杂的问题。

She does ___not ___have ___the ___faintest ___idea how to solve this complex problem.