I don't know how to study hard early, but I regret learning late.

It is easy for young people to learn, but difficult for old people. Every inch of time is an inch of light.

An inch of time is an inch of gold, saving money is hard to buy time.

If a person doesn't work hard when he is young, he will regret when he is old ―― laziness when he is young will make him regret when he is old; Reckless youth makes regretful old age; Idle youth, poor old age