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to gnaw; to nibble; to bite; to munch; to crunch
to dabble in; to know a little bit about; to learn a little of; to have a smattering of
ネズミがチーズをかじっている音がした。
I heard the sound of a mouse nibbling cheese.
リスが木の実をかじる姿はかわいい。
A squirrel nibbling on nuts is cute.
犬が骨をかじって遊んでいるのを見た。
I saw a dog playing by gnawing on a bone.