( ( Most texts ) ( ( ( define chemistry ) ( as ( ( the science ) ( concerned ( with ( ( the study ) ( of ( ( matter and ) ( its changes ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJS Most) (NNS texts)) (VP (VB define) (NP (NN chemistry)) (PP (IN as) (NP (NP (DT the) (NN science)) (VP (VBN concerned) (PP (IN with) (NP (NP (DT the) (NN study)) (PP (IN of) (NP (NP (NN matter)) (CC and) (NP (PRP$ its) (NNS changes)))))))))) (. .)))
Most texts define chemistry as the science concerned with the study of matter and its changes.
(ROOT (S (NP (NNP Chemistry)) (VP (VBZ is) (VP (VBN defined) (PP (IN as) (NP (NP (DT the) (NN study)) (PP (IN of) (NP (NN matter))))))) (. .)))