( ( Four valves ) ( ( ( assist ( with ( ( the flow ) ( of blood ) ) ) ) ( through ( the heart ) ) ) . ) )
(ROOT (S (NP (CD Four) (NNS valves)) (VP (VB assist) (PP (IN with) (NP (NP (DT the) (NN flow)) (PP (IN of) (NP (NN blood))))) (PP (IN through) (NP (DT the) (NN heart)))) (. .)))
Four valves assist with the flow of blood through the heart.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD four) (NNS valves)) (PP (IN in) (NP (DT the) (NN heart))))) (. .)))