( ( ( Perfect combustion ) ( of propane ) ) ( ( yields ( ( water , ) ( ( ( carbon dioxide ) & ) heat ) ) ) . ) )
(ROOT (S (NP (NP (NNP Perfect) (NNP combustion)) (PP (IN of) (NP (NN propane)))) (VP (VBZ yields) (NP (NP (NN water)) (, ,) (NP (NP (NN carbon) (NN dioxide)) (CC &) (NP (NN heat))))) (. .)))
Perfect combustion of propane yields water, carbon dioxide &amp; heat.
(ROOT (S (NP (NP (DT The) (NN combustion)) (PP (IN of) (NP (NN propane) (NN gas)))) (VP (VBZ produces) (NP (NP (NN carbon) (NN dioxide)) (CC and) (NP (NN water) (NN vapor)))) (. .)))