that fails to make adequate 
(ROOT (S (NP (DT that)) (VP (VBZ fails) (S (VP (TO to) (VP (VB make) (S (ADJP (JJ adequate)))))))))
(ROOT (S (NP (DT )) (VP (VBZ ) (S (VP (TO ) (VP (VB ) (S (ADJP (JJ )))))))))