mouth是可数名词。
mouth：n.嘴；口；需要供养的人；入口；
mouth的复数形式是mouths
Her mouth felt as dry as a bone.
她感到口干舌燥。
Don't talk with your mouth full.
不要一边吃一边说话。
She opened her mouth to say something.
她张开嘴要说什么。
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