( ( A ( voltaic cell ) ) ( ( ( utilizes ( a ( spontaneous ( oxidation-reduction reaction ) ) ) ) ( to ( produce ( electrical energy ) ) ) ) . ) )
(ROOT (S (NP (DT A) (JJ voltaic) (NN cell)) (VP (VBZ utilizes) (NP (DT a) (JJ spontaneous) (JJ oxidation-reduction) (NN reaction)) (S (VP (TO to) (VP (VB produce) (NP (JJ electrical) (NN energy)))))) (. .)))
A voltaic cell utilizes a spontaneous oxidation-reduction reaction to produce electrical energy.
(ROOT (S (NP (DT A) (JJ voltaic) (NN cell)) (VP (VBZ generates) (NP (DT an) (JJ electric) (NN current)) (PP (IN through) (NP (NP (DT a) (NN reaction)) (VP (VBN known) (PP (IN as) (NP (DT a) (PRN (-LRB- -LRB-) (NP (NN n)) (-RRB- -RRB-)) (JJ spontaneous) (NN redox))))))) (. .)))