年少誰不賤
[nián shăo shuí bù jiàn]
This phrase humorously reflects that being frivolous or mischievous during one’s youth is quite common, expressing that almost everyone has gone through this stage in life. Note: This could be interpreted as offensive in certain contexts because of using the word 賤 (jian), but contextually here means naughtiness and lack of seriousness.