( It ( ( will ( ( ( produce energy ) ( in ( ( the form ) ( of ( ( electricity and ) heat ) ) ) ) ) ( ( as long ) ( as ( ( ( its fuel ) ( -- ( hydrogen -- ) ) ) ( is supplied ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (MD will) (VP (VB produce) (NP (NN energy)) (PP (IN in) (NP (NP (DT the) (NN form)) (PP (IN of) (NP (NN electricity) (CC and) (NN heat))))) (ADVP (ADVP (RB as) (RB long)) (SBAR (IN as) (S (NP (NP (PRP$ its) (NN fuel)) (PRN (: --) (NP (NN hydrogen)) (: --))) (VP (VBZ is) (VP (VBN supplied)))))))) (. .)))
It will produce energy in the form of electricity and heat as long as its fuel--hydrogen--is supplied.
(ROOT (S (NP (NNP Heat)) (VP (VBZ is) (VP (VBN produced) (SBAR (WHADVP (WRB when)) (S (NP (NN paper)) (VP (VBZ is) (VP (VBN burned))))))) (. .)))
Heat is produced when paper is burned.