狐狸未成精只因太年轻
[hú lí wèi chéng jīng zhĭ yīn tài nián qīng]
Literal translation means 'The fox hasn’t become a spirit yet because it's too young.' Here ‘fox’ refers to fox spirits which appear in East Asian folktales as magical beings. It suggests someone is not fully grown or experienced due to youthfulness.