you wish you had n't seen 
(ROOT (S (NP (PRP you)) (VP (VBP wish) (SBAR (S (NP (PRP you)) (VP (VBD had) (RB n't) (VP (VBN seen))))))))
(ROOT (S (NP (PRP )) (VP (VBP ) (SBAR (S (NP (PRP )) (VP (VBD ) (RB ) (VP (VBN ))))))))