其中一些学生上大学了还显得很不成熟。

Some of the students seem quite ___immature for university.

他把她的担忧当作不成熟而不予理会。

He dismissed her concerns as ___immature and refused to listen.

在商务会议上那样反应有点幼稚。

Reacting like that in a business meeting was rather ___immature.