自然,當然,本然
Naturalness \Nat"u*ral*ness\, n. The state or quality of being natural; conformity to nature.
naturalness n 1: the quality of being natural or based on natural principles; "he accepted the naturalness of death"; "the spontaneous naturalness of his manner" [ant: {unnaturalness}] 2: the quality of innocent naivete [syn: {artlessness}, {innocence}, {ingenuousness}]