( Today ( , ( ( volcanic ( carbon dioxide ) ) ( ( is ( ( kept ( in check ) ) ( by ( ( natural processes ) ( such ( as ( ( chemical weathering ) ( of ( ( rocks , ) ( which ( ( removes ( the gas ) ) ( from ( ( the atmosphere ) ( in ( ( the form ) ( of ( carbonate minerals ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (NP (NN Today)) (, ,) (NP (JJ volcanic) (NN carbon) (NN dioxide)) (VP (VBZ is) (VP (VBN kept) (PP (IN in) (NP (NN check))) (PP (IN by) (NP (NP (JJ natural) (NNS processes)) (PP (JJ such) (IN as) (NP (NP (NN chemical) (NN weathering)) (PP (IN of) (NP (NP (NNS rocks)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ removes) (NP (DT the) (NN gas)) (PP (IN from) (NP (NP (DT the) (NN atmosphere)) (PP (IN in) (NP (NP (DT the) (NN form)) (PP (IN of) (NP (JJ carbonate) (NNS minerals)))))))))))))))))) (. .)))
Today, volcanic carbon dioxide is kept in check by natural processes such as chemical weathering of rocks, which removes the gas from the atmosphere in the form of carbonate minerals.
(ROOT (S (NP (JJ Volcanic) (NNS gases)) (VP (VBP helpe) (S (VP (TO to) (VP (VB form) (NP (DT the) (NN atmosphere)) (PP (IN on) (NP (NN earth))))))) (. .)))