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diligent; hard-working; industrious
彼の勤勉な姿勢は周囲から高く評価されている。
His diligent attitude is highly valued by those around him.
勤勉さこそが成功への近道だと祖父に教わった。
My grandfather taught me that diligence is the shortcut to success.
勤勉に働く人には必ず報いがあると信じている。
I believe hardworking people will definitely be rewarded.