and night
assiduously
bec et ongles
chronically
committedly
day after day
decidedly
decisively
determinedly
devotedly
diligently
doggedly
earnestly
enduringly
faithfully
firmly
fixedly
for an age
for life
for long
frequently
habitually
hammer and tongs
heart and soul
hour after hour
in all seriousness
in earnest
in good earnest
indefatigably
industriously
inflexibly
insistently
interminably
inveterately
like a bulldog
like a leech
long
long ago
long since
loyally
month after month
morning
noon
obstinately
patiently
perseveringly
persistingly
pertinaciously
ploddingly
protractedly
consistently