( ( Illustrate ( ( the motion ) ( of ( ( an object ) ( using ( a ( graph ( to ( ( show ( ( a change ) ( in position ) ) ) ( over ( ( a period ) ( of time ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (VP (VB Illustrate) (NP (NP (DT the) (NN motion)) (PP (IN of) (NP (NP (DT an) (NN object)) (VP (VBG using) (NP (DT a) (NN graph) (S (VP (TO to) (VP (VB show) (NP (NP (DT a) (NN change)) (PP (IN in) (NP (NN position)))) (PP (IN over) (NP (NP (DT a) (NN period)) (PP (IN of) (NP (NN time)))))))))))))) (. .)))
Illustrate the motion of an object using a graph to show a change in position over a period of time.
(ROOT (S (NP (NNP Line) (NNS graphs)) (VP (VBP are) (ADJP (RB especially) (JJ useful) (PP (IN for) (S (VP (VBG showing) (NP (NNS changes)) (PP (IN over) (NP (NN time)))))))) (. .)))