狗嘴里吐不出象牙

Explanation: Mouth can not say good things bad analogy. 　　Usage: Complex sentence; as object clause; for ridicule and jokes 　　Source: Yuan High Wenxiu "encounter Emperor" First off: "and this other thing, what good words, say what is justice, the dog mouth seldom speaks." 　　Examples: This is something my father and what other good things, say what axioms, ~. ("Emperor of Yuan election meets" the first break) Thesaurus:  dog South of the great wall Spit ivory