that you want to slap it 
(ROOT (SBAR (IN that) (S (NP (PRP you)) (VP (VBP want) (S (VP (TO to) (VP (VB slap) (NP (PRP it)))))))))
(ROOT (SBAR (IN ) (S (NP (PRP )) (VP (VBP ) (S (VP (TO ) (VP (VB ) (NP (PRP )))))))))