(of a period of time) long

not long (after); before too long; soon; soon after

(coll.) for a long time

everlasting; perpetual; lasting; forever; permanent

long-time; long-term; lasting; enduring; permanent; for a long time

before long; soon after

lasting; enduring; persistent; permanent; protracted; endurance; persistence; to last long

already a long time

not long ago; not long before

for a long time; for ages

long (tradition, history etc)

long-established; time-honored

enduring while the world lasts (idiom); eternal

for a very long time

a very long time (etymology: in mathematics, n represents an arbitrarily large number)

constant; persistent; long-lasting; eternal

with the passage of time; over time

to accumulate over time

in the end; eventually

long-lasting; durable

durable; long-lasting

a good while; a long time

an instant or an eternity

period of ... years

after a long time (idiom)

protracted (idiom); long and drawn-out

see 友誼地久天長|友谊地久天长[You3 yi4 di4 jiu3 tian1 chang2]