| persistent(adjective, strain, firmness, labour, hardiness) |
| firm(adjective, strain, firmness, labour, hardiness) |
| stable(adjective, strain, firmness, labour, hardiness) |
| enduring(verb, adjective, strain, firmness, labour) |
| lasting(verb, adjective, strain, firmness, labour) |
| lingering(verb, adjective, strain, firmness, labour) |
| constant(adjective, strain, firmness, labour, hardiness) |
| long-standing(adjective, strain, firmness, labour, hardiness) |
| permanent(adjective, strain, firmness, labour, hardiness) |
| perpetual(adjective, strain, firmness, labour, hardiness) |
| steady(adjective, strain, firmness, labour, hardiness) |
| durable(adjective, strain, firmness, labour, hardiness) |
| quiescent(adjective, strain, firmness, labour, hardiness) |
| rigid(adjective, strain, firmness, labour, hardiness) |
| stationary(adjective, strain, firmness, labour, hardiness) |
| steadfast(adjective, strain, firmness, labour, hardiness) |
| sustained(adjective, strain, firmness, labour, hardiness) |
| remaining(noun, verb, adjective, end, check) |
| stopping(noun, verb, adjective, end, check) |
| continuing(verb, adjective, split, familiar, extra) |