( ( Calculate ( the ( elastic ( potential energy ) ) ) ) . )
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Calculate the elastic 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))) (. .)))