 Oh, you want a cracker! 
( Oh ( , ( you ( ( want ( a cracker ) ) ! ) ) ) )
(ROOT (S (INTJ (UH Oh)) (, ,) (NP (PRP you)) (VP (VBP want) (NP (DT a) (NN cracker))) (. !)))
I know. You don't want a cracker.
( ( I ( know . ) ) ( You ( ( ( do n't ) ( want ( a cracker ) ) ) . ) ) )
(ROOT (S (S (NP (PRP I)) (VP (VBP know)) (. .)) (NP (PRP You)) (VP (VBP do) (RB n't) (VP (VB want) (NP (DT a) (NN cracker)))) (. .)))