( Most ( ( ( cartilaginous fish ) ( ( pump ( water ( over ( their gills ) ) ) ) ( by ( ( ( expanding and ) contracting ) ( their ( mouth ( ( cavity and ) pharynx ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJS Most)) (VP (VBZ cartilaginous) (RB fish) (VP (VB pump) (NP (NP (NN water)) (PP (IN over) (NP (PRP$ their) (NNS gills)))) (PP (IN by) (S (VP (VBG expanding) (CC and) (VBG contracting) (NP (PRP$ their) (NN mouth) (NN cavity) (CC and) (NN pharynx))))))) (. .)))
Most cartilaginous fish pump water over their gills by expanding and contracting their mouth cavity and pharynx.
(ROOT (S (NP (NNP Jaws) (CC and) (NN pharynx) (NNS muscles)) (VP (VBP are) (VP (VBN used) (S (VP (TO to) (VP (VB pump) (NP (NN water)) (PP (IN over) (NP (DT the) (NNS gills)))))))) (. .)))