唇亡齒寒

- （比喻利害關(guān)系十分密切） If the lips are gone，the teeth will be cold. -- share a common lot; If one of two interdependent things falls，the other is in danger.; Teeth are exposed [cold] when lips are lost.; The lips being lost, the teeth feel cold -- When the lips are lost, the teeth will be exposed to the cold.; (two countries) which are so closely related that they have common interests and share same fate; With bared lips, the teeth feel cold.