How could she have been so foolish as to fall in love with him?

她怎么这么傻，竟爱上了他？

《牛津词典》

How could I ever be foolish enough to expect a renewal of his love?

我怎么蠢到这般地步，竟会指望他重新爱上我？

youdao

Have a love of life is happy, life for love is foolish.

有爱情的生活是幸福的，为爱情而生活是愚蠢的。

youdao

No grander, more foolish declaration of love has been seen, or heard, in recent cinema.

NEWYORKER: Blue Valentine

Finally, there is this notion that telling a teenage girl that she is being dumb for falling in love or foolish for giving up her dreams is going to actually work.

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There's just an assumption that these benefits are positive, that the big time is worth it, that expensive coaches and conference expansion and mega TV contracts all serve a greater good networks and fans love it, and it's foolish to not want a piece.

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