( ( ( ( ( ( ( Their hearts ) ( have ( ( ( three or ) four ) chambers ) ) ) , ) and ) ( , ( ( like humans ) , ) ) ) ( they ( breathe ( through lungs ) ) ) ) . )
(ROOT (S (S (NP (PRP$ Their) (NNS hearts)) (VP (VBP have) (NP (QP (CD three) (CC or) (CD four)) (NNS chambers)))) (, ,) (CC and) (PRN (, ,) (PP (IN like) (NP (NNS humans))) (, ,)) (S (NP (PRP they)) (VP (VB breathe) (PP (IN through) (NP (NNS lungs))))) (. .)))
Their hearts have three or four chambers, and, like humans, they breathe through lungs.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD three) (NNS chambers)) (PP (IN in) (NP (DT an) (NN amphibian) (NN heart))))) (. .)))