十字开头的年龄都似懂非懂
[shí zì kāi tóu de nián líng dōu sì dŏng fēi dŏng]
'Ages that start with ten are half understood.' This nickname implies a time of transition, typically referring to the teenage years or adolescence, where one is between innocence and wisdom - they're starting to comprehend life's nuances but still do not completely grasp everything.