the perch had to been them , on .
(ROOT_0 (S_0 (ATS_3 (NP_1 (DT_0 the) (NN_2 perch)) (VP_4 (ATVP_0 (VP_5 (VBD_2 had) (S_2 (VP_0 (TO_0 to) (VP_1 (VBN_0 been) (NP_1 (PRP_0 them)))))) (COMMA_0 ,)) (PRT_0 (RP_0 on)))) (DOT_0 .)))