| numberless(adjective, complete, constant, absolute, monotonous) |
| steady(adjective, determined, regular, persistent, constant) |
| unbroken(adjective, steady, persistent, constant, monotonous) |
| boring(adjective, tedious, dreary, drab, endless) |
| countless(adjective, complete, constant, absolute, abundant) |
| dateless |
| dull(adjective, flat, stupid, dry, dead) |
| extended(adjective, steady, stable, regular, tedious) |
| extensive(adjective, great, complete, absolute, huge) |
| long-drawn-out(adjective, slow, late, endless, rambling) |
| long-winded(adjective, slow, tedious, late, long) |
| nonstop(adjective, direct, continue, persistent, constant) |
| perennial(adjective, continuous, durable) |
| recurrent(adjective, continuous) |
| relentless(adjective, continue, determined, steady, persistent) |
| uniform(adjective, persistent, continuous, endless, relentless) |
| ageless |
| continued(adjective, continued) |
| enduring(adjective, determined, steady, persistent, constant) |
| no end of(verb, expression, adjective, idiom, phrasal verb) |