一寸光阴一寸金，寸金难买寸光阴
yī​cùn​guāng​yīn​yī​cùn​jīn​cùn​jīn​nán​mǎi​cùn​guāng​yīn

time is precious

一寸光阴一寸金，寸金难买寸光阴 一寸光陰一寸金，寸金難買寸光陰 yī​cùn​guāng​yīn​yī​cùn​jīn​cùn​jīn​nán​mǎi​cùn​guāng​yīn
time is precious
Literally "an inch of time is worth an inch of gold, but an inch of gold cannot buy that inch of time"; used as a proverb to emphasize that time is extremely valuable and cannot be bought back once lost.