( ( Each ( normal human ) ) ( ( has ( ( 23 pairs ) ( of chromosomes ) ) ) ; ) )
(ROOT (S (NP (DT Each) (JJ normal) (NN human)) (VP (VBZ has) (NP (NP (CD 23) (NNS pairs)) (PP (IN of) (NP (NNS chromosomes))))) (: ;)))
Each normal human has 23 pairs of chromosomes;
(ROOT (S (NP (NNS Humans)) (ADVP (RB typically)) (VP (VBP have) (NP (NP (CD 23) (JJ pairs) (NNS pairs)) (PP (IN of) (NP (NNS chromosomes))))) (. .)))
Humans typically have 23 pairs pairs of chromosomes.