( Food ( ( enters ( ( the mouth ) ( where ( ( ( the ( first stage ) ) ( in ( the ( digestive process ) ) ) ) ( ( ( takes place ) , ) ( with ( ( ( ( the action ) ( of ( the tongue ) ) ) and ) ( ( the secretion ) ( of saliva ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Food)) (VP (VBZ enters) (NP (NP (DT the) (NN mouth)) (SBAR (WHADVP (WRB where)) (S (NP (NP (DT the) (JJ first) (NN stage)) (PP (IN in) (NP (DT the) (JJ digestive) (NN process)))) (VP (VBZ takes) (NP (NN place)) (, ,) (PP (IN with) (NP (NP (NP (DT the) (NN action)) (PP (IN of) (NP (DT the) (NN tongue)))) (CC and) (NP (NP (DT the) (NN secretion)) (PP (IN of) (NP (NN saliva))))))))))) (. .)))
Food enters the mouth where the first stage in the digestive process takes place, with the action of the tongue and the secretion of saliva.
(ROOT (S (NP (DT The) (NN mouth)) (VP (VBZ is) (NP (DT the) (JJ first) (NN digestive) (NN organ)) (SBAR (IN that) (S (NP (NN food)) (VP (VBZ enters))))) (. .)))