( Mammals ( ( possess ( ( ( a ( four-chambered heart ) ) and ) ( a ( double-loop ( circulatory system ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Mammals)) (VP (VBP possess) (NP (NP (DT a) (JJ four-chambered) (NN heart)) (CC and) (NP (DT a) (JJ double-loop) (NN circulatory) (NN system)))) (. .)))
Mammals possess a four-chambered heart and a double-loop circulatory system.
(ROOT (S (PP (IN Like) (NP (NP (DT all) (NNS tetrapods)) (PP (IN except) (NP (NNS birds) (CC and) (NNS mammals))))) (, ,) (NP (NNS frogs)) (VP (VBP possess) (NP (NP (DT a) (NN heart)) (PP (IN with) (NP (CD three) (NNS chambers))))) (. .)))