Breakdown of La joven llegó a alcanzar una fama impensable.
joven
young / young person
un
a, an, some
alcanzar
to reach
a
linking word before an infinitive (after 'to burst out')
llegar a
to manage to, to go so far as to (+ infinitive)
impensable
unthinkable
la fama
the fame; the reputation (to have a reputation for)
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