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to work hard; to try hard; to strive; to endeavour; to endeavor; to devote oneself to; to make an effort; to be zealous
彼は毎日練習に励んで上達を目指しているそうだ。
He apparently strives at practice every day aiming to improve.
学業に励む学生には奨学金が支給される制度がある。
There's a system to provide scholarships to students who work hard at their studies.
健康管理に励むことで病気を予防できる。
You can prevent illness by diligently managing your health.