狗嘴吐不出象牙

[gǒu zuǐ tǔ bù chū xiàng yá]

[释义]
» [look not for musk in dogs kennel;a dogs mouth emits no ivory] 比喻坏人口里说不出好话。也作狗嘴长不出象牙

[英文]
no ivory issues from the mouth of a dog