opera on film is never satisfactory . 
(ROOT (S (NP (NP (NN opera)) (PP (IN on) (NP (NN film)))) (VP (VBZ is) (ADVP (RB never)) (ADJP (JJ satisfactory))) (. .)))
(ROOT (S (NP (NP (NN )) (PP (IN ) (NP (NN )))) (VP (VBZ ) (ADVP (RB )) (ADJP (JJ ))) (. )))