( ( ( ( Most protist ) diseases ) ( in humans ) ) ( ( are ( caused ( by protozoa ) ) ) . ) )
(ROOT (S (NP (NP (ADJP (RBS Most) (JJ protist)) (NNS diseases)) (PP (IN in) (NP (NNS humans)))) (VP (VBP are) (VP (VBN caused) (PP (IN by) (NP (NN protozoa))))) (. .)))
Most protist diseases in humans are caused by protozoa.
(ROOT (S (NP (NP (JJ Protist) (NNS diseases)) (PP (IN in) (NP (NNS humans)))) (VP (VBP are) (VP (VBN caused) (PP (IN by) (NP (NN protozoa))))) (. .)))