这是我听过的最愚蠢的主意。

This is the ___stupidest idea I've ever heard.

我又把咖啡洒在键盘上了——真是蠢到家了！

I spilled coffee on my keyboard again—how ___stupid is that!

这是我听过最无聊的笑话，一点都不好笑。

That's the ___stupidest joke I've ever heard—it's not funny at all.