them was studied to was back of a something structures to rattle .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 them)) (VP_4 (VBD_1 was) (VP_2 (VBN_0 studied) (S_2 (VP_0 (TO_0 to) (VP_1 (ATVP_3 (VBD_1 was) (ADJP_0 (JJ_1 back) (PP_1 (IN_1 of) (NP_2 (ATNP_0 (DT_0 a) (NN_3 something)) (NP_4 (NNS_1 structures)))))) (S_2 (VP_0 (TO_0 to) (VP_1 (VB_0 rattle)))))))))) (DOT_0 .)))