Juvenile
juvenile /ˈdʒu:vənaɪl/
n. 青少年
adj. 青少年的,幼稚的,年少无知的
It refers to a child or young person who is not yet old enough to be regarded as an adult; or refers to someone's behaviour which is silly or childish.
它指的是还没有到成人年龄的孩子或年轻人;或指某人的行为举止过于愚蠢、幼稚。
Nowadays, juvenile crime is increasing at a terrifying rate.
现如今,青少年犯罪正在以惊人的速度增长。
To be honest, their behavior was juvenile.
说实话,他们的行为很幼稚。