Naive 是形容词，名词是naivety。 naive 英[naɪˈi:v] 美[nɑˈiv] adj. 天真的; 幼稚的; 单纯的; [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 must have been naive to think ...
laughter：笑声（名词） laugh：大笑（动词）