story refer , <apostrophe><apostrophe> a friend wore doing back .
(ROOT_0 (S_0 (ATS_3 (ATS_1 (ATS_2 (ATS_0 (S_1 (NP_0 (NN_2 story)) (VP_5 (VBP_0 refer))) (COMMA_0 ,)) (APOSTROPHE_0 <apostrophe><apostrophe>)) (NP_0 (DT_0 a) (NN_2 friend))) (VP_3 (VBD_1 wore) (VP_2 (VBG_0 doing) (NP_2 (RB_1 back))))) (DOT_0 .)))