that is wickedly fun to watch 
(ROOT (S (NP (DT that)) (VP (VBZ is) (ADJP (RB wickedly) (JJ fun) (SBAR (S (VP (TO to) (VP (VB watch)))))))))
(ROOT (S (NP (DT )) (VP (VBZ ) (ADJP (RB ) (JJ ) (SBAR (S (VP (TO ) (VP (VB )))))))))