三十年河东，三十年河西
sān​shí​nián​hé​dōng​sān​shí​nián​hé​xī

change is the only constant

三十年河东，三十年河西 三十年河東，三十年河西 sān​shí​nián​hé​dōng​sān​shí​nián​hé​xī
change is the only constant
(proverb) the river flows thirty years to the east and thirty years to the west; used to describe the ever-changing nature of the world where fortunes rise and fall over time