( ( Potential energy ) ( ( is ( energy ( ( stored internally ) ( in ( an object ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Potential) (NN energy)) (VP (VBZ is) (NP (NP (NN energy)) (VP (VBN stored) (ADVP (RB internally)) (PP (IN in) (NP (DT an) (NN object)))))) (. .)))
Potential energy is energy stored internally in an object.
(ROOT (S (NP (NP (NNP Energy)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (VP (VBN stored) (PP (IN in) (NP (DT a) (NN person) (CC or) (NN object)))))))) (VP (VBZ is) (VP (VBN called) (NP (JJ potential) (NN energy)))) (. .)))