( ( Enzymes ( in ( your mouth ) ) ) ( ( ( begin ( the ( digestive process ) ) ) ( by ( ( breaking carbohydrates ) ( into ( their ( small ( , ( constituent parts ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNS Enzymes)) (PP (IN in) (NP (PRP$ your) (NN mouth)))) (VP (VBP begin) (NP (DT the) (JJ digestive) (NN process)) (PP (IN by) (S (VP (VBG breaking) (NP (NNS carbohydrates)) (PP (IN into) (NP (PRP$ their) (JJ small) (, ,) (JJ constituent) (NNS parts))))))) (. .)))
Enzymes in your mouth begin the digestive process by breaking carbohydrates into their small, constituent parts.
(ROOT (S (NP (JJ Carbohydrate) (NN digestion)) (VP (VBZ begins) (PP (IN in) (NP (DT the) (NN mouth)))) (. .)))