( ( Ulcers ( in ( ( the duodenum ) ( -LRB- ( ( ( the ( first part ) ) ( of ( the ( small intestine ) ) ) ) -RRB- ) ) ) ) ) ( ( are ( ( the ( ( most common ) cause ) ) ( of ( bleeding ( in ( the ( upper ( digestive tract ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNS Ulcers)) (PP (IN in) (NP (NP (DT the) (NN duodenum)) (PRN (-LRB- -LRB-) (NP (NP (DT the) (JJ first) (NN part)) (PP (IN of) (NP (DT the) (JJ small) (NN intestine)))) (-RRB- -RRB-))))) (VP (VBP are) (NP (NP (DT the) (ADJP (RBS most) (JJ common)) (NN cause)) (PP (IN of) (S (VP (VBG bleeding) (PP (IN in) (NP (DT the) (JJ upper) (NN digestive) (NN tract)))))))) (. .)))
Ulcers in the duodenum (the first part of the small intestine) are the most common cause of bleeding in the upper digestive tract.
(ROOT (S (NP (JJS Most) (NNS digestion)) (VP (VBZ is) (VP (VBN completed) (PP (IN in) (NP (DT the) (NN duodenum))))) (. .)))