it should below keep remains while them had a charge teeth .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_1 it)) (VP_4 (ATVP_1 (MD_0 should) (ADVP_0 (RB_0 below))) (VP_1 (VB_0 keep) (VP_2 (VBZ_0 remains) (SBAR_0 (IN_2 while) (S_1 (NP_1 (PRP_0 them)) (VP_5 (VBD_1 had) (NP_3 (ATNP_0 (DT_0 a) (NN_3 charge)) (NNS_0 teeth))))))))) (DOT_0 .)))