How do you say "I don't know" without sounding, well, dumb?

要怎样说“我不知道”才能让自己听上去不傻？

youdao

M: Well, you can call her a bimbo. Bimbo is a very dumb woman, not necessarily a blonde.

你的意思是，bimbo可以指笨的女人，不管她是不是金发女郎。

youdao

Here in America, well, if we throw away a perfectly good 200-year-old credit rating, that'll be pretty dumb, but nobody's killing each other yet.

在美国，如果我们丢掉了200多年来的完美的信用评级，那会是非常糟糕的事情，但是也没有人会互相残杀。

youdao

But if you're running for President, making fun of yourself for being dumb is, well, dumb.

CNN: He ain't dumb, he's my president

That's a guy that's playing really well for us, but that's a dumb penalty.

WSJ: Capitals top Rangers 2-1 in OT, take series lead

Thor was the big, dumb summer fun movie, while Captain America was the weighty, well-written movie serious fans drool over.

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