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to hold in one's mouth
to bring with; to take along
犬がボールを口にくわえて走ってきた。
The dog came running with a ball in its mouth.
パイプをくわえたまま新聞を読んでいた。
He was reading the newspaper with a pipe in his mouth.
猫がネズミをくわえている。
The cat is holding a mouse in its mouth.