They told about a conference When .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 They)) (VP_4 (VBN_0 told) (PP_0 (IN_1 about) (NP_2 (NP_5 (DT_0 a) (NN_2 conference)) (FRAG_0 (WHADVP_0 (WRB_0 When))))))) (DOT_0 .)))