( ( Thanks ( to ( ( the processes ) ( of photosynthesis ) ) ) ) ( , ( they ( ( ( renew ( ( the ( oxygen stock ) ) ( in ( the atmosphere ) ) ) ) ( by ( ( ( fixing ( atmospheric ( carbon dioxide ) ) ) and ) ( moderating ( the ( so-called ( greenhouse effect ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (VBG Thanks) (PP (TO to) (NP (NP (DT the) (NNS processes)) (PP (IN of) (NP (NN photosynthesis)))))) (, ,) (NP (PRP they)) (VP (VB renew) (NP (NP (DT the) (NN oxygen) (NN stock)) (PP (IN in) (NP (DT the) (NN atmosphere)))) (PP (IN by) (S (VP (VP (VBG fixing) (NP (JJ atmospheric) (NN carbon) (NN dioxide))) (CC and) (VP (VBG moderating) (NP (DT the) (JJ so-called) (NN greenhouse) (NN effect))))))) (. .)))
Thanks to the processes of photosynthesis, they renew the oxygen stock in the atmosphere by fixing atmospheric carbon dioxide and moderating the so-called greenhouse effect.
(ROOT (S (NP (NP (DT The) (NN process)) (ADJP (JJ responsible) (PP (IN for) (NP (NP (DT the) (NN presence)) (PP (IN of) (NP (NP (NN oxygen)) (PP (IN in) (NP (PRP$ our) (NN atmosphere))))))))) (VP (VBZ is) (NP (NN photosynthesis))) (. .)))