'I don't know what happened, exactly.' I said.
( ' ( ( ( ( ( I ( ( do n't ) ( know ( what ( ( happened , ) exactly ) ) ) ) ) . ) ' ) ( I said ) ) . ) )
(ROOT (S ('' ') (S (NP (PRP I)) (VP (VBP do) (RB n't) (VP (VB know) (SBAR (WHNP (WP what)) (S (VP (VBD happened) (, ,) (ADVP (RB exactly)))))))) (. .) ('' ') (S (NP (PRP I)) (VP (VBD said))) (. .)))
You aren't making sense.
( You ( ( ( are n't ) ( making sense ) ) . ) )
(ROOT (S (NP (PRP You)) (VP (VBP are) (RB n't) (VP (VBG making) (NP (NN sense)))) (. .)))