| foolish(silly, crazy, thoughtless, impulsive, unwise) |
| foot-in-mouth(adjective, careless, bold, thoughtless, impulsive) |
| frantic(adjective, violent, cruel, vicious, brutal) |
| frenzied(adjective, careless, thoughtless, impulsive, reckless) |
| froward(adjective, passionate, unstable, unpredictable, unreliable) |
| gladiatorial(difficult, irritable, turbulent, belligerent, argumentative) |
| gruff |
| grumpy |
| hard-core |
| have chip on shoulder(expression, idiom, difficult, turbulent, belligerent) |
| heated |
| high-strung(unstable, unpredictable, unreliable, fickle, erratic) |
| hothead |
| hyper(adjective, passionate, unstable, unpredictable, unreliable) |
| hypersensitive(adjective, passionate, unstable, unpredictable, unreliable) |
| hysterical(adjective, passionate, cruel, crazy, vicious) |
| ill-judged(adjective, careless, foolish, bold, thoughtless) |
| ill-natured |
| immature(careless, thoughtless, impulsive, reckless, hasty) |
| impassioned(adjective, difficult, passionate, cruel, crazy) |