nevertheless efficiently amusing for a good while 
(ROOT (S (ADVP (RB nevertheless)) (ADJP (RB efficiently) (VBG amusing)) (PP (IN for) (NP (DT a) (JJ good) (NN while)))))
(ROOT (S (ADVP (RB )) (ADJP (RB ) (VBG )) (PP (IN ) (NP (DT ) (JJ ) (NN )))))