They gnaw on trees and harm them.

它们啃食并伤害树木。

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Dogs like to gnaw on a bone.

狗爱啃骨头。

《新英汉大辞典》

Pets may also gnaw on electrical cords for Christmas-tree lights.

宠物也会因啃咬彩灯的电线而触电。

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The catch is that you have to be invested in order to gnaw on it.

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The dogs prance around in Santa outfits from Petco, dine on doggy cakes from Three Dog Bakery, and gnaw on rawhide bones tucked into their stockings.

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Children may also feel better if they gnaw on chilled, but not frozen, teething rings or safe toys made of rubber, unpainted wood or cotton terrycloth.

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