( Motion ( ( can ( be ( ( determined ( by ( change ( in position ) ) ) ) ( over time ) ) ) ) . ) )
(ROOT (S (NP (NNP Motion)) (VP (MD can) (VP (VB be) (VP (VBN determined) (PP (IN by) (NP (NP (NN change)) (PP (IN in) (NP (NN position))))) (PP (IN over) (NP (NN time)))))) (. .)))
Motion can be determined by change in position over time.
(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)))))))) (. .)))