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to be careful; to be discreet
to do in moderation; to refrain (from overdoing); to abstain
to be reverent
to be purified; to be chaste
健康のために飲酒を慎むよう医師に勧められた。
The doctor advised me to be moderate with alcohol for the sake of my health.
公共の場では大声での会話を慎むべきである。
One should refrain from loud conversation in public places.
発言を慎んでいたが、最終的に意見を述べることにした。
I had been holding back my words, but ultimately decided to voice my opinion.