こつこつと (translations)→ slowly steadily
せっせと (translations)→ active assiduously busily constantly diligently duly dutifully heartily industriously systematic systematically voraciously
周到に (translations)→ careful carefully meticulously
丹念に (translations)→ attentively clever closely examination faithfully methodically neatly patiently thoroughly
念入りに (translations)→ checkup further perfectly scrupulous splendidly thorough
