quicksand

n.流沙；陷阱

A mule won't sink in quicksand but a donkey will. 骡子不会陷入流沙中,但是驴子会。

Is it true that a man who steps into quicksand is doomed to die? 掉入流沙中的人就注定会死去吗？

Vanity is the quicksand of reason. 虚荣乃理学之流沙。

Conceit is the quicksand of success. 自负是成功的流沙。