( This ( ( ( causes ( blood ( ( pressure and ) volume ) ) ) ( to decrease ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ causes) (NP (NN blood) (NN pressure) (CC and) (NN volume)) (S (VP (TO to) (VP (VB decrease))))) (. .)))
This causes blood pressure and volume to decrease.
(ROOT (S (S (VP (VBG Reducing) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS molecules)) (PP (IN in) (NP (DT a) (JJ rigid) (NN container)))))))) (VP (VBZ causes) (NP (NN pressure)) (S (VP (TO to) (VP (VB decrease))))) (. .)))