behaviour that is not sensible and is typical of people who are much younger （行为）不成熟的，不够老练的，幼稚的 emotional immaturity 情绪不成熟
the state of not being fully developed or grown 未长成的；发育未全的 the immaturity of renal function in some infants 一些婴儿肾功能的不成熟
opposite maturity