( They ( ( contain ( a ( three ( chambered heart ) ) ) ) . ) )
(ROOT (S (NP (PRP They)) (VP (VBP contain) (NP (DT a) (CD three) (NN chambered) (NN heart))) (. .)))
They contain a three chambered heart.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD three) (NNS chambers)) (PP (IN in) (NP (DT a) (JJ reptiles) (NN heart))))) (. .)))