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to hold in one's mouth
to bring with; to take along
猫が魚をくわえて逃げていった。
The cat ran off with a fish in its mouth.
赤ちゃんがおもちゃをくわえている。
The baby has a toy in its mouth.
ペンをくわえながら考え込んでいた。
I was deep in thought with a pen in my mouth.