( ( ( ( The ( dry wood ) ) ( is ( ( ( a store ) ( of ( ( chemical energy ) . ) ) ) ( ( As ( it ( burns ( in ( the fireplace ) ) ) ) ) ( , ( ( chemical energy ) ( is ( ( ( released and ) converted ) ( to ( ( ( ( thermal energy ) ( -LRB- ( heat -RRB- ) ) ) and ) ( light energy ) ) ) ) ) ) ) ) ) ) ) . ) ( Notice ( that ( ( the wood ) ( now ( turns ( into ( ashes ( -LRB- ( ( a ( new substance ) ) -RRB- ) ) ) ) ) ) ) ) ) )
(ROOT (FRAG (NP (NP (DT The) (JJ dry) (NN wood)) (SBAR (S (VP (VBZ is) (NP (NP (DT a) (NN store)) (PP (IN of) (FRAG (NP (NN chemical) (NN energy)) (. .))) (SBAR (S (SBAR (IN As) (S (NP (PRP it)) (VP (VBZ burns) (PP (IN in) (NP (DT the) (NN fireplace)))))) (, ,) (NP (NN chemical) (NN energy)) (VP (VBZ is) (VP (VBN released) (CC and) (VBN converted) (PP (TO to) (NP (NP (NP (JJ thermal) (NN energy)) (PRN (-LRB- -LRB-) (NP (NN heat)) (-RRB- -RRB-))) (CC and) (NP (JJ light) (NN energy)))))))))))) (. .)) (X (NP (NNP Notice)) (SBAR (IN that) (S (NP (DT the) (NN wood)) (ADVP (RB now)) (VP (VBZ turns) (PP (IN into) (NP (NP (NNS ashes)) (PRN (-LRB- -LRB-) (NP (DT a) (JJ new) (NN substance)) (-RRB- -RRB-))))))))))
The dry wood is a store of chemical energy. As it burns in the  fireplace, chemical energy is released and converted to thermal energy  (heat) and light energy. Notice that the wood now turns into ashes (a new substance)
(ROOT (S (NP (NP (DT The) (NN action)) (PP (IN of) (S (VP (VBG burning) (NP (NP (DT a) (NN piece)) (PP (IN of) (NP (NN wood)))))))) (VP (VBZ forms) (NP (DT a) (JJ different) (NN chemical) (NN substance))) (. .)))