Unable to keep fluid down.
 Patient has nausea
(ROOT (S (S (ADJP (JJ Unable) (S (VP (TO to) (VP (VB keep) (NP (NN fluid)) (PRT (RB down))))))) (. .)))
(ROOT (S (NP (NN Patient)) (VP (VBZ has) (NP (NN nausea)))))
( ( Unable ( to ( ( keep fluid ) down ) ) ) . )
( Patient ( has nausea ) )