an old head on young shoulders
Young and sincere, Chinese idiom, Pinyin is sh ǎ oni á NL ǎ och é ng, which means that although people are young, they are very experienced. The same as "young and old". It comes from chapter 29 of biography of heroes and heroines by Wen Kang of Qing Dynasty.
The origin of Idioms
Chapter 29 of the story of heroes and Heroines: "Yulang is no longer the young and sincere Yulang you and I first met in Nengren temple."
Idiom usage
He is young and steady
Chinese PinYin : shǎo nián lǎo chéng
an old head on young shoulders
put the cart before the horse. chē zài mǎ qián
Let the wind and waves rise, sit in Diaoyutai. rèn píng fēng làng qǐ,wěn zuò diào yú tái