They stifled what A boy was at .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 They)) (VP_4 (VBD_0 stifled) (SBAR_0 (WHNP_0 (WP_0 what)) (S_1 (NP_0 (DT_0 A) (NN_2 boy)) (VP_5 (VBD_1 was) (PP_1 (IN_1 at))))))) (DOT_0 .)))