It was a very foolish thing to do.

干那种事很蠢。

《牛津词典》

I can't do the foolish thing.

我不能这样做愚蠢的事。

youdao

It's not like him to have done such a foolish thing.

这么愚蠢的事情不像是他做的。

youdao

That would, of course, be a very bad and foolish thing for the Kremlin to do.

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There is to be a single police service from the 1st of April - and you know the foolish thing?

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"He's done a foolish thing ... but you cannot condemn a man who has been tempted by many women, " she said.

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