( ( ( ( ( ( ( ( ( ( e.g. , ) chemical ) , ) elastic ) , ) gravitational ) , ) and ) nuclear ) ( ( are ( ( all types ) ( of ( potential energy ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP e.g.)) (, ,) (NP (NN chemical)) (, ,) (NP (NN elastic)) (, ,) (NP (JJ gravitational)) (, ,) (CC and) (NP (JJ nuclear))) (VP (VBP are) (NP (NP (DT all) (NNS types)) (PP (IN of) (NP (JJ potential) (NN energy))))) (. .)))
e.g., chemical, elastic, gravitational, and nuclear are all types of potential energy.
(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))) (. .)))