| serious(adjective, sober, resolute, persistent, unwavering) |
| set(adjective, serious, resolute, persistent, unwavering) |
| set on(expression, adjective, serious, resolute, persistent) |
| settled(adjective, intense, deliberate, determined, serious) |
| single-minded(adjective, intense, deliberate, cruel, determined) |
| solemn(adjective, thoughtful, sober, serious, sincere) |
| solid(adjective, serious, resolute, persistent, pat) |
| somber(adjective, thoughtful, sober, serious, sincere) |
| stable(adjective, thoughtful, sober, serious, sincere) |
| staid(adjective, thoughtful, sober, serious, sincere) |
| steadfast(adjective, intense, deliberate, determined, serious) |
| steady(adjective, intense, deliberate, determined, thoughtful) |
| strong-minded(adjective, determined, serious, resolute, persistent) |
| strong-willed(adjective, intense, deliberate, determined, serious) |
| telelogical(intense, deliberate, determined, resolute, focused) |
| tenacious(adjective, intense, deliberate, determined, serious) |
| undeviating(intense, deliberate, determined, resolute, focused) |
| unfaltering(adjective, intense, deliberate, determined, serious) |
| unflinching(adjective, serious, resolute, persistent, unwavering) |
| unhesitating(adjective, serious, resolute, persistent, unwavering) |