( ( For example ) ( , ( ( ( go ( over ( the ( nervous system ) ) ) ) ( when ( ( learning ( about ( ( the ( circulatory system ) ) ( since ( the ( nervous system ) ) ) ) ) ) ( ( plays ( a ( big role ) ) ) ( in ( regulating ( the ( ( circulation and ) heart ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN For) (NP (NN example))) (, ,) (VP (VB go) (PP (IN over) (NP (DT the) (JJ nervous) (NN system))) (SBAR (WHADVP (WRB when)) (S (S (VP (VBG learning) (PP (IN about) (NP (NP (DT the) (JJ circulatory) (NN system)) (PP (IN since) (NP (DT the) (JJ nervous) (NN system))))))) (VP (VBZ plays) (NP (DT a) (JJ big) (NN role)) (PP (IN in) (S (VP (VBG regulating) (NP (DT the) (NN circulation) (CC and) (NN heart))))))))) (. .)))
For example, go over the nervous system when learning about the circulatory system since the nervous system plays a big role in regulating the circulation and heart.
(ROOT (S (NP (DT The) (JJ nervous) (NN system)) (VP (VBZ plays) (NP (NP (DT a) (JJ critical) (NN role)) (PP (IN in) (NP (NP (DT the) (NN regulation)) (PP (IN of) (NP (NN vascular) (NNS homeostasis))))))) (. .)))