( ( ( ( It ( is ( a ( transport system ) ) ) ) and ) ( ( many ( other systems ) ) ( ( rely ( on ( the ( circulatory system ) ) ) ) ( to ( move materials ) ) ) ) ) . )
(ROOT (S (S (NP (PRP It)) (VP (VBZ is) (NP (DT a) (NN transport) (NN system)))) (CC and) (S (NP (JJ many) (JJ other) (NNS systems)) (VP (VBP rely) (PP (IN on) (NP (DT the) (JJ circulatory) (NN system))) (S (VP (TO to) (VP (VB move) (NP (NNS materials))))))) (. .)))
It is a transport system and many other systems rely on the circulatory system to move materials.
(ROOT (S (NP (NP (DT The) (JJ main) (NN function)) (PP (IN of) (NP (DT the) (JJ circulatory) (NN system)))) (VP (VBZ is) (S (VP (TO to) (VP (VB transport) (NP (NNS materials)))))) (. .)))