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to hold in one's mouth
to bring with; to take along
犬がボールを咥えて走ってきた。
The dog came running with a ball in its mouth.
犬が公園で拾った棒をしっかり咥えた。
The dog firmly held a stick it picked up at the park in its mouth.
猫が台所から盗んだ魚を咥えている。
The cat is holding a fish it stole from the kitchen in its mouth.