plenty to impress about e.t. 
(ROOT (NP (NP (NN plenty)) (SBAR (S (VP (TO to) (VP (VB impress) (PP (IN about) (NP (NNP e.t))))))) (. .)))
(ROOT (NP (NP (NN )) (SBAR (S (VP (TO ) (VP (VB ) (PP (IN ) (NP (NNP ))))))) (. )))