( ( Elastic energy ) ( ( is ( ( the ( total ( potential ( and ( kinetic energy ) ) ) ) ) ( in ( a system ) ) ) ) . ) )
(ROOT (S (NP (JJ Elastic) (NN energy)) (VP (VBZ is) (NP (NP (DT the) (JJ total) (NN potential) (CC and) (JJ kinetic) (NN energy)) (PP (IN in) (NP (DT a) (NN system))))) (. .)))
Elastic energy is the total potential and kinetic energy in a system.
(ROOT (S (S (VP (VBG Changing) (NP (NP (DT the) (NN shape)) (PP (IN of) (NP (DT an) (JJ elastic) (NN material)))))) (VP (VBZ gives) (NP (PRP it)) (NP (JJ potential) (NN energy))) (. .)))