( There ( ( ( are also ) ( ( four valves ) ( which ( ( regulate or ) ( ( control ( ( the flow ) ( of blood ) ) ) ( within ( the heart ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (EX There)) (VP (VBP are) (ADVP (RB also)) (NP (NP (CD four) (NNS valves)) (SBAR (WHNP (WDT which)) (S (VP (VP (VB regulate)) (CC or) (VP (VB control) (NP (NP (DT the) (NN flow)) (PP (IN of) (NP (NN blood)))) (PP (IN within) (NP (DT the) (NN heart))))))))) (. .)))
There are also four valves which regulate or control the flow of blood within the heart.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD four) (NNS valves)) (PP (IN in) (NP (DT the) (NN heart))))) (. .)))