a sentimental but entirely irresistible portrait 
(ROOT (NP (DT a) (ADJP (ADJP (JJ sentimental)) (CC but) (ADJP (RB entirely) (JJ irresistible))) (NN portrait)))
(ROOT (NP (DT ) (ADJP (ADJP (JJ )) (CC ) (ADJP (RB ) (JJ ))) (NN )))