assiduously
bullheadedly
devotedly
diligently
faithfully
headstrongly
indefatigably
industriously
insistently
loyally
obstinately
patiently
perseveringly
persistently
persistingly
pertinaciously
ploddingly
relentlessly
resolutely
sedulously
sloggingly
stubbornly
sullenly
tenaciously
tirelessly
unabatingly
uncooperatively
unfalteringly
unflaggingly
unflinchingly
unintermittingly
uninterruptedly
unregenerately
unrelentingly
unremittingly
unrestingly
unsleepingly
unswervingly
untiringly
unwaveringly
unwearyingly
wearilessly
willfully
with set jaw