( ( ( A ( chemical reaction ) ) ( occurring ( in ( ( green plants ) ( ( in which ) ( ( ( ( ( carbon ( ( dioxide and ) water ) ) , ) ( in ( ( the presence ) ( of ( ( chlorophyll and ) light ) ) ) ) ) , ) ( combine ( to ( produce ( a ( ( carbohydrate and ) oxygen ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (NP (NP (DT A) (JJ chemical) (NN reaction)) (VP (VBG occurring) (PP (IN in) (NP (NP (JJ green) (NNS plants)) (SBAR (WHPP (IN in) (WHNP (WDT which))) (S (NP (NP (NN carbon) (NN dioxide) (CC and) (NN water)) (, ,) (PP (IN in) (NP (NP (DT the) (NN presence)) (PP (IN of) (NP (NN chlorophyll) (CC and) (NN light))))) (, ,)) (VP (VBP combine) (S (VP (TO to) (VP (VB produce) (NP (DT a) (NN carbohydrate) (CC and) (NN oxygen))))))))))) (. .)))
A chemical reaction occurring in green plants in which carbon dioxide and water, in the presence of chlorophyll and light, combine to produce a carbohydrate and oxygen.
(ROOT (S (NP (NNP Combustion) (NNS reactions)) (VP (VBP involve) (S (NP (NP (DT the) (NN reaction)) (PP (IN of) (NP (NP (DT a) (NN hydrocarbon)) (PP (IN with) (NP (NN oxygen) (NN gas)))))) (VP (TO to) (VP (VB produce) (NP (NN water) (CC and) (NN carbon) (NN dioxide)))))) (. .)))