人不风流枉年少人不犯二枉少年
[rén bù fēng liú wăng nián shăo rén bù fàn èr wăng shăo nián]
If one does not live frivolously in youth then they wasted their youth and likewise if they do not act stupidly when young they also wasted their youth. Reflects cultural expectations regarding indulgence and exuberance during younger years.