一寸光阴一寸金 An inch of time is an inch of gold. The line comes from the Tang poet Wang Zhenbai: “Reading, I did not notice that spring was already deep. An inch of time is an inch of gold.”
少壮不努力,老大徒伤悲 If one does not strive when young, one grieves in vain when old. The lines end the anonymous Han poem Long Song. “A hundred rivers flow east to the sea. When will they return west?”