( ( Growth spurt ) ( ( ( ( ( occurs , ) ( on average ) ) , ) ( ( ( two years ) earlier ) ( in ( females ( than males ) ) ) ) ) . ) )
(ROOT (S (NP (NN Growth) (NN spurt)) (VP (VBZ occurs) (, ,) (PP (IN on) (NP (NN average))) (, ,) (PP (ADVP (NP (CD two) (NNS years)) (RBR earlier)) (IN in) (NP (NP (NNS females)) (PP (IN than) (NP (NNS males)))))) (. .)))
Growth spurt occurs, on average, two years earlier in females than males.
(ROOT (S (NP (JJ Female) (NN gender)) (ADVP (RB typically)) (VP (VBZ experiences) (NP (NN growth) (NNS spurts)) (ADVP (RB first))) (. .)))