◎沧海桑田cānghǎi-sāngtián
[the swift changes of the world;great changes are seen in the course of time;the evanescence of the worldly affairs is like the sea turned into a mulberry field (orchid)] 大海变成了种桑树的田地，种桑树的田地变成了大海。比喻世事多变，人生无常;或喻世事变化的巨大迅速——略称沧桑
山河改转，沧海桑田