( Motion ( ( is ( ( the change ) ( in ( ( the position ) ( of ( an ( extended thing ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Motion)) (VP (VBZ is) (NP (NP (DT the) (NN change)) (PP (IN in) (NP (NP (DT the) (NN position)) (PP (IN of) (NP (DT an) (VBN extended) (NN thing))))))) (. .)))
Motion is the change in the position of an extended thing.
(ROOT (S (NP (NNP Motion)) (VP (MD can) (VP (VB be) (VP (VBN defined) (ADVP (RB simply)) (PP (IN as) (NP (NP (DT a) (NN change)) (PP (IN in) (NP (NN position)))))))) (. .)))