continued
long
abiding
age-long
aged
ancient
antique
articulated
assiduous
catenated
ceaseless
changeless
chronic
concatenated
connected
constant
continual
continuous
cyclical
diligent
direct
diuturnal
dogged
durable
during
endless
enduring
evergreen
faithful
featureless
firm
fixed
frozen
gapless
hardy
immediate
immobile
immutable
inalterable
incessant
indefatigable
indomitable
industrious
insistent
intact
interminable
intransient
inveterate
discontinuing