Diligent; showing steady, hardworking, and conscientious effort.
彼女はとても勤勉で、毎日夜遅くまで勉強している。
She is very diligent and studies late every night.
勤勉な学生は少しずつ力を伸ばしていく。
A diligent student improves little by little.
会社は勤勉さを評価して、昇進の機会を与えた。
The company valued his diligence and gave him a promotion opportunity.