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(ROOT_0 (S_0 (ATS_3 (ATS_1 (ATS_2 (ATS_3 (ATS_1 (TICK_0 ``) (NP_1 (PRP_0 I))) (VP_3 (VBD_0 was))) (DOT_0 .)) (NP_0 (PRP_1 they))) (VP_3 (VBD_1 used) (VP_2 (VBN_0 listened) (PP_0 (IN_1 of) (NP_2 (NN_3 gravel)))))) (DOT_0 .)))