( ( In reality ) ( , ( ( both types ) ( ( ( are ( nuclear energy ) ) ( because ( they ( involve ( ( the energy ) ( that ( ( holds atoms ) together ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NN reality))) (, ,) (NP (DT both) (NNS types)) (VP (VBP are) (NP (JJ nuclear) (NN energy)) (SBAR (IN because) (S (NP (PRP they)) (VP (VBP involve) (NP (NP (DT the) (NN energy)) (SBAR (WHNP (WDT that)) (S (VP (VBZ holds) (NP (NNS atoms)) (ADVP (RB together)))))))))) (. .)))
In reality, both types are nuclear energy because they involve the energy that holds atoms together.
(ROOT (S (NP (NN Bond) (NN energy)) (VP (VBZ holds) (NP (NNS atoms)) (ADVP (RB together))) (. .)))
Bond energy holds atoms together.