na-adjective, noun
simple; naive; unsophisticated
Describes a person, idea, or thing that is plain, unpretentious, and sometimes innocent to the point of being naive. Can be positive (unaffected simplicity) or mildly negative (lacking sophistication).
彼の素朴な質問に、みんなが笑顔になった。
His simple question made everyone smile.
この村には素朴な風景が残っている。
An unspoiled landscape remains in this village.