| immature(careless, thoughtless, impulsive, reckless, hasty) |
| impavid(strong, tough, bold, spirited, brave) |
| impractical(adjective, happy, tender, perfect, fantastic) |
| indomitable(strong, tough, noble, bold, spirited) |
| industrious(adjective, energetic, daring, resourceful, innovative) |
| insuppressible(careless, thoughtless, impulsive, reckless, hasty) |
| irrational(careless, thoughtless, impulsive, reckless, hasty) |
| irresponsible(adjective, careless, wild, bold, thoughtless) |
| itching(adjective, energetic, daring, resourceful, innovative) |
| jaunty |
| jumping to conclusions(expression, idiom, careless, thoughtless, impulsive) |
| keen(adjective, smart, energetic, elegant, fashionable) |
| lively(adjective, smart, energetic, elegant, fashionable) |
| lusting(adjective, energetic, daring, resourceful, innovative) |
| madbrain |
| madbrained |
| martial(strong, tough, bold, spirited, brave) |
| match |
| mysterious(adjective, happy, tender, perfect, fantastic) |
| nasty |