( ( After ( they ( reached adulthood ) ) ) ( , ( I ( ( ( divided them ) ( into ( three groups ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN After) (S (NP (PRP they)) (VP (VBD reached) (ADJP (JJ adulthood))))) (, ,) (NP (PRP I)) (VP (VBD divided) (NP (PRP them)) (PP (IN into) (NP (CD three) (NNS groups)))) (. .)))
After they reached adulthood, I divided them into three groups.
(ROOT (S (NP (NNP Adulthood)) (VP (VBZ is) (VP (VBN divided) (PP (IN into) (NP (CD three) (NNS stages))))) (. .)))