babyish
adj. 幼稚的；愚蠢的；适于婴儿的
例句
I'm ashamed of the babyish nonsense I write.
我为我写出幼稚的话感到丢脸。
《柯林斯英汉双解大词典》
If your child regresses to babyish behaviour, all you know for certain is that the child is under stress.
如果你的孩子退步到幼稚的行为，你可以肯定的是孩子正处在压力之下。
The boy has outgrown babyish habits.
那男孩已长大，不再有稚气。
