| persistent(adjective, continue, strain, determined, usual) |
| constant(adjective, sound, continue, strain, determined) |
| endless(adjective, sound, continue, determined, steady) |
| permanent(adjective, strain, usual, steady, stable) |
| everlasting(adjective, continue, steady, stable, fixed) |
| stable(adjective, strain, steady, regular, fixed) |
| consistent(adjective, strain, usual, steady, stable) |
| firm(adjective, strain, determined, familiar, steady) |
| unfluctuating(adjective, strain, steady, stable, regular) |
| sound(adjective, strain, firmness, labour, hardiness) |
| lasting(adjective, strain, stable, fixed, firmness) |
| eternal(adjective, continue, pause, steady, fixed) |
| enduring(adjective, strain, determined, familiar, steady) |
| incessant(adjective, sound, continue, determined, steady) |
| ceaseless(adjective, sound, continue, steady, persistent) |
| unceasing(adjective, continue, steady, persistent, constant) |
| steady(adjective, strain, determined, familiar, usual) |
| unending(adjective, continue, steady, persistent, constant) |
| invariable(adjective, strain, steady, stable, regular) |
| durable(adjective, strain, firmness, labour, hardiness) |