( ( Through ( ( the process ) ( of photosynthesis ) ) ) ( , ( oxygen ( ( ( combines ( with ( ( carbon and ) hydrogen ) ) ) ( to ( form ( plant carbohydrates ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN Through) (NP (NP (DT the) (NN process)) (PP (IN of) (NP (NN photosynthesis))))) (, ,) (NP (NN oxygen)) (VP (VBZ combines) (PP (IN with) (NP (NN carbon) (CC and) (NN hydrogen))) (S (VP (TO to) (VP (VB form) (NP (NN plant) (NNS carbohydrates)))))) (. .)))
Through the process of photosynthesis , oxygen combines with carbon and hydrogen to form plant carbohydrates .
(ROOT (S (NP (NNP Carbohydrate)) (VP (VBZ contains) (NP (NN carbon) (, ,) (NN hydrogen) (, ,) (CC and) (NN oxygen)) (PP (IN in) (NP (NP (DT a) (NN ratio)) (PP (IN of) (NP (CD 1:2:1)))))) (. .)))