N3 - 改善かいぜん
betterment, improvement
N2 - 改めてあらためて
another time, again, over again, anew, formally
N2 - 改めるあらためる
to change, to alter, to reform, to revise
N2 - 改札かいさつ
examination of tickets
N2 - 改正かいせい
revision, amendment, alteration
N2 - 改造かいぞう
(1) remodeling, (2) modding (comp)
N1 - 改まるあらたまる
to be renewed
N1 - 改悪かいあく
deterioration, changing for the worse
N1 - 改革かいかく
reform, reformation, innovation
N1 - 改修かいしゅう
repair, improvement
N1 - 改良かいりょう
improvement, reform