菇凉你还年轻别把身体用旧
[gū liáng nĭ hái nián qīng bié bă shēn tĭ yòng jiù]
In an affectionate tone to young girls, it warns them not to over exhaust themselves or abuse their bodies while they're still young, for health reasons. ('Gu Liang' is slang term to refer girls affectionately.)