Well, who told you that story?
( Well ( , ( who ( ( ( told you ) ( that story ) ) ? ) ) ) )
(ROOT (SBARQ (NP (NNP Well)) (, ,) (WHNP (WP who)) (SQ (VBD told) (NP (PRP you)) (NP (DT that) (NN story))) (. ?)))
You have forgotten who it was that told that story to you, haven't you?
( ( You ( have ( forgotten ( who ( it ( was ( that ( ( told ( that story ) ) ( to you ) ) ) ) ) ) ) ) ) ( , ( ( ( have n't ) you ) ? ) ) )
(ROOT (S (S (NP (PRP You)) (VP (VBP have) (VP (VBN forgotten) (SBAR (WHNP (WP who)) (S (NP (PRP it)) (VP (VBD was) (SBAR (IN that) (S (VP (VBD told) (NP (DT that) (NN story)) (PP (TO to) (NP (PRP you)))))))))))) (, ,) (VP (VBP have) (RB n't)) (NP (PRP you)) (. ?)))