| fierce(adjective, keen, passionate, enthusiastic, fervent) |
| fiery(adjective, keen, passionate, enthusiastic, fervent) |
| fixed(adjective, firm, solid, stable, resolute) |
| hot(adjective, keen, passionate, enthusiastic, fervent) |
| hungry(adjective, keen, passionate, enthusiastic, fervent) |
| immobile(adjective, intense, resolute, persistent, dedicated) |
| immovable(adjective, firm, solid, intense, stable) |
| impassioned(adjective, keen, passionate, enthusiastic, fervent) |
| imperturbable(adjective, firm, sensible, solid, steady) |
| in good faith(expression, adjective, idiom, firm, honest) |
| incessant |
| inexorable(adjective, intense, resolute, persistent, dedicated) |
| inflexible(adjective, resolute, persistent, reliable, steadfast) |
| influential |
| intent(adjective, resolute, persistent, dedicated, unwavering) |
| just(adjective, close, correct, honest, pure) |
| keen(adjective, passionate, enthusiastic, fervent) |
| levelheaded(adjective, firm, sensible, solid, steady) |
| liege man(expression, idiom) |
| lifelike(adjective, close, correct, true, realistic) |