why long time ago cant differnate boy and girl?

u see those old china show everytime is like that

Si mi dai ji…?

u damn sart hor, come out with differnate

Shocked Shocked Shocked Shocked Shocked

Laughing

they haven’t learn integration or dy/dx yet…

Don't underestimate ancient China

last time sch teach stupid poem ma…never teach maths..

When boy and girl reach age 11-13 they start to develop their organs and become different le~