Denshi Jisho — Online Japanese dictionary

努力 どりょく great effort; exertion; endeavour; endeavor; effort
Common word, Noun, Suru verb 
努力 どりょくか hard worker; hardworking person
Noun 
努力 どりょくしょう prize awarded for a person's effort
Noun 
努力奮励 どりょくふんれい making strenuous efforts; exerting oneself
Noun, Suru verb 
努力も空しく どりょくもむなしく after efforts in vain
Noun 
努力も虚しく どりょくもむなしく after efforts in vain
Noun 

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