( ( The ( pulmonary veins ) ) ( then ( ( ( ( carry ( the ( oxygen-enriched blood ) ) ) ( from ( the lungs ) ) ) ( back ( to ( ( the ( left side ) ) ( of ( ( the heart ) ( where ( it ( is ( distributed ( throughout ( the body ) ) ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (DT The) (JJ pulmonary) (NNS veins)) (ADVP (RB then)) (VP (VBP carry) (NP (DT the) (JJ oxygen-enriched) (NN blood)) (PP (IN from) (NP (DT the) (NNS lungs))) (ADVP (RB back) (PP (TO to) (NP (NP (DT the) (JJ left) (NN side)) (PP (IN of) (NP (NP (DT the) (NN heart)) (SBAR (WHADVP (WRB where)) (S (NP (PRP it)) (VP (VBZ is) (VP (VBN distributed) (PP (IN throughout) (NP (DT the) (NN body))))))))))))) (. .)))
The pulmonary veins then carry the oxygen-enriched blood from the lungs back to the left side of the heart where it is distributed throughout the body.
(ROOT (S (SBAR (IN After) (S (NP (NP (DT the) (NN blood)) (PP (IN in) (NP (DT the) (JJ pulmonary) (NNS capillaries)))) (VP (VBZ becomes) (VP (VBN saturated) (PP (IN with) (NP (NN oxygen))))))) (, ,) (NP (PRP it)) (VP (VBZ leaves) (NP (NP (DT the) (NNS lungs) (CC and) (NNS travels)) (PP (TO to) (NP (DT the) (NN heart))))) (. .)))