Synonyms and related words :
arduously, atrociously, barbarously, bec et ongles, bestially, brutally, brutishly, committedly, decidedly, decisively, determinedly, devotedly, earnestly, effortfully, ferociously, fiercely, firmly, fixedly, hammer and tongs, hard, heart and soul, in all seriousness, in earnest, in good earnest, industriously, inflexibly, inhumanly, laboriously, like a bulldog, like a leech, manfully, mercilessly, obstinately, operosely, perseveringly, persistently, pitilessly, purposefully, relentlessly, resolutely, resolvedly, ruthlessly, savagely, seriously, sincerely, singlemindedly, staunchly, steadfastly, steadily, strenuously, tenaciously, the hard way, toilsomely, unswervingly, unyieldingly, viciously, wholeheartedly, with a will, with constancy, with effort, with total dedication