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(ROOT_0 (S_0 (ATS_3 (ATS_1 (ATS_2 (TICK_0 ``) (ADVP_0 (RB_1 back) (RB_1 back))) (NP_0 (PRP_1 you))) (VP_3 (VBD_0 did) (NP_3 (ATNP_0 (DT_0 an) (VBN_0 blackened)) (POS_0 <apostrophe>s)))) (DOT_0 .)))