I puzzled over the problem for ages before the light suddenly dawned.

我对这个问题冥思苦想了很久才豁然开朗。

《牛津词典》

I puzzled over it for a time and eventually I was able to think of another equation which would get over the logical difficulties of the negative probabilities.

我为此困惑过一段时间，最终我得以想到另一个方程，这个方程可以克服负概率的逻辑困难。

youdao

I was genuinely puzzled.

我真的是感到很困惑。

youdao

Like many others, I was puzzled by the new color combination (blue and orange, really?).

FORBES: Redesign the IRS Web Site

Moreover, I am puzzled by what appears to be the core of his message.

BBC: Are Republicans the 'stupid party'?

And I was aware of it, and as a child I was puzzled by it.

WSJ: The Weekend Interview with Julian Fellowes: The Anti-Snobbery of 'Downton Abbey'