| from the hip(expression, adjective, idiom, simple, natural) |
| get off(verb, expression, craft, plan, create) |
| go off half-cocked(expression, idiom) |
| gone off deep end(expression, idiom, thoughtless, impetuous, unwary) |
| haphazard |
| hatch(verb, make, fix, plan, produce) |
| head trip(verb, expression, craft, plan, create) |
| headlong(thoughtless, impetuous, unwary) |
| hot-and-cold(thoughtless, impetuous, unwary) |
| imagine(verb, craft, plan, produce, create) |
| immediate(free, casual, impulsive, spontaneous, unprepared) |
| impetuous(adjective, simple, passionate, violent, natural) |
| improvisatory(free, fake, casual, impulsive, spontaneous) |
| improviso(free, spontaneous, unprepared, impromptu, unplanned) |
| impulsive(adjective, adverb, simple, natural, casual) |
| inevitable(adjective, simple, natural, casual, impulsive) |
| informal(adjective, free, casual, impulsive, spontaneous) |
| instinctive(adjective, simple, passionate, violent, natural) |
| intrigue(verb, plan, create, arrange, design) |
| involuntary(adjective, simple, passionate, violent, natural) |