She mumbled to forced back who to speak down .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 She)) (VP_4 (VBD_2 mumbled) (S_2 (VP_0 (TO_0 to) (VP_1 (ATVP_0 (VBD_2 forced) (ADVP_0 (RB_0 back))) (SBAR_0 (WHNP_0 (WP_0 who)) (S_2 (VP_0 (TO_0 to) (VP_1 (VB_0 speak) (PRT_0 (RP_0 down))))))))))) (DOT_0 .)))