artlessness

她回答时的坦率纯真让所有人都放下了戒心。

The ___artlessness of her reply made everyone let down their guard.

他的画作因缺乏雕琢而透出一种动人的天真。

His paintings move viewers with their touching ___artlessness.

我被这孩子话语里的纯真质朴深深打动。

I was deeply moved by the ___artlessness in this child's words.