advanced
early
a bit previous
ahead
bright
developed
far ahead
forward
gifted
half-baked
half-cocked
hasty
ill-considered
impulsive
intelligent
mature
not firm
overhasty
oversoon
precipitate
premature
previous
quick
rushed
smart
soon
too early
too soon
uncrystallized
unjelled
unmatured
unmeditated
unpremeditated
unprepared
unripe
untimely
apt
disobedient
exceptional
excitable
good-looking
headstrong
imaginative
immature
impetuous
impressionable
inexperienced
mischievous
perceptive
sensitive
thoughtless
versatile
wayward
atrocious
ferocious
backward
dull
serotinous
stupid