( ( The duodenum ) ( ( ( ( precedes ( the ( ( jejunum and ) ileum ) ) ) and ) ( is ( ( the ( shortest part ) ) ( of ( ( ( the ( small intestine ) ) , ) ( where ( ( most ( chemical digestion ) ) ( takes place ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN duodenum)) (VP (VP (VBZ precedes) (NP (DT the) (NN jejunum) (CC and) (NN ileum))) (CC and) (VP (VBZ is) (NP (NP (DT the) (JJS shortest) (NN part)) (PP (IN of) (NP (NP (DT the) (JJ small) (NN intestine)) (, ,) (SBAR (WHADVP (WRB where)) (S (NP (JJS most) (NN chemical) (NNS digestion)) (VP (VBZ takes) (NP (NN place)))))))))) (. .)))
The duodenum precedes the jejunum and ileum and is the shortest part of the small intestine, where most chemical digestion takes place.
(ROOT (S (NP (JJS Most) (NNS digestion)) (VP (VBZ is) (VP (VBN completed) (PP (IN in) (NP (DT the) (NN duodenum))))) (. .)))