( ( Blood ( from ( the lungs ) ) ) ( ( enters ( ( the ( left atrium ) ) ( of ( the heart ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP Blood)) (PP (IN from) (NP (DT the) (NNS lungs)))) (VP (VBZ enters) (NP (NP (DT the) (JJ left) (NN atrium)) (PP (IN of) (NP (DT the) (NN heart))))) (. .)))
Blood from the lungs enters the left atrium of the heart.
(ROOT (S (NP (NP (NNP Blood)) (PP (IN from) (NP (DT the) (NNS lungs)))) (VP (VBZ enters) (PP (IN into) (NP (DT the) (JJ left) (NN atrium)))) (. .)))