( It ( can ( be ( converted ( into ( ( ( light energy ) , ) ( ( ( mechanical energy ) , ) ( heat ( energy etc ) ) ) ) ) ) ) ) )
(ROOT (S (NP (PRP It)) (VP (MD can) (VP (VB be) (VP (VBN converted) (PP (IN into) (NP (NP (JJ light) (NN energy)) (, ,) (NP (NP (JJ mechanical) (NN energy)) (, ,) (NP (NN heat) (NN energy) (NN etc))))))))))
It can be converted into light energy, mechanical energy, heat energy etc
(ROOT (S (S (NP (DT The) (NN energy)) (VP (VBZ transformations) (SBAR (IN that) (S (VP (VBP occur) (SBAR (WHADVP (WRB when)) (S (NP (DT a) (NN candle) (NNS burns)) (VP (VBZ is) (VP (VBN described) (PP (IN by))))))))))) (: :) (S (NP (NP (NN chemical) (NN energy)) (PP (IN from) (NP (DT the) (NN wax)))) (VP (VBZ is) (VP (VBN converted) (PP (IN into) (NP (NN light) (CC and) (NN heat) (NN energy)))))) (. .)))