adamantly
bec et ongles
bona fide
close
closely
committedly
compactly
consistently
constantly
deafeningly
decidedly
decisively
densely
determinedly
devotedly
dourly
earnestly
faithfully
fast
firm
fixedly
forcefully
forcibly
grimly
hammer and tongs
hardly
heart and soul
heartily
heavily
immovably
immutably
imperviously
implacably
impliably
impregnably
in all seriousness
in earnest
in good earnest
in good faith
inexorably
inflexibly
inseparably
intensely
intransigently
invincibly
invulnerably
ironhandedly
irreconcilably
irresistibly
like a bulldog