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to wonder; to puzzle oneself about; to feel anxious about; to suspect; to doubt
刑事は彼女のアリバイを訝った。
The detective was suspicious of her alibi.
隣人は不審な物音を訝って、警察に通報した。
The neighbor, suspicious of the strange noises, reported them to the police.
読者は、作者の真意を訝るほかないと感じた。
Readers could not help but wonder about the author's true intentions.