naive
adj.缺乏经验的;幼稚的;无知的;轻信的;天真的;率直的;稚拙派的(简单质朴，色彩明快)

【例句】
It's naive to think that teachers are always tolerant.
认为老师们总那么宽容是幼稚的。

I can't believe you were so naive as to trust him!
真是难以相信你会幼稚到信任他！