His mother doesn't allow him to get in with the wrong crowd of boys.

他母亲不让他与一群坏孩子交往。

《新英汉大辞典》

It is going to be tempting for you to mix with the wrong crowd.

你想和一群错误的人混在一起。

youdao

That led me to the street and the gangs, the wrong crowd for sure.

我开始流浪街头和与朋党为伍，这些人肯定是一群损友。

youdao

The essay indicated he was a complex teen, who acknowledged hanging with the wrong crowd during his sophomore and junior years.

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He explained how he had ended up homeless after losing his job as a baker and falling in with the wrong crowd.

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Guilty or not, his story is every parent's nightmare: what could happen when a son or daughter spends his or her adolescence far from home and falls in with the wrong crowd.

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