( ( The cells ) ( ( ( ( use ( the oxygen ) ) , ) ( ( ( giving off ) ( carbon dioxide ) ) ( as ( a ( waste product ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNS cells)) (VP (VBP use) (NP (DT the) (NN oxygen)) (, ,) (S (VP (VBG giving) (PRT (RP off)) (NP (NN carbon) (NN dioxide)) (PP (IN as) (NP (DT a) (NN waste) (NN product)))))) (. .)))
The cells use the oxygen, giving off carbon dioxide as a waste product.
(ROOT (S (PP (IN In) (NP (DT the) (NN body))) (, ,) (S (NP (NN oxygen)) (VP (VBZ is) (VP (VBN used) (PP (IN by) (NP (NP (NNS cells)) (PP (IN of) (NP (NP (DT the) (NN body) (POS 's)) (NNS tissues)))))))) (CC and) (S (NP (NN carbon) (NN dioxide)) (VP (VBZ is) (VP (VBN produced) (PP (IN as) (NP (DT a) (NN waste) (NN product)))))) (. .)))