sort of thing, nature

ぜんぜん

not at all

とうぜん

naturally, of course

ぐうぜん

coincidence, by chance

しぜん

nature, natural

とつぜん

suddenly

いぜん

still, as yet

てんねん

nature, spontaneity

しぜんかがく

natural science

こうぜん

openly

せいぜん

orderly, regular, well-organized

だんぜん

firmly, absolutely, definitely

ばくぜん

obscure, vague, equivocal

ぼうぜん

dumbfounded, overcome with surprise

ひつぜん

inevitable, necessary