They could keep The warm spray over snow .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 They)) (VP_4 (MD_0 could) (VP_1 (VB_0 keep) (NP_3 (NP_6 (ATNP_1 (DT_0 The) (JJ_1 warm)) (NN_1 spray)) (PP_0 (IN_1 over) (NP_2 (NN_3 snow))))))) (DOT_0 .)))