on a world of snow , the boy looks on dirt .
(ROOT_0 (S_0 (ATS_3 (ATS_1 (ATS_2 (PP_2 (IN_0 on) (NP_3 (NP_5 (DT_0 a) (NN_2 world)) (PP_0 (IN_1 of) (NP_2 (NN_3 snow))))) (COMMA_0 ,)) (NP_0 (DT_0 the) (NN_2 boy))) (VP_3 (VBZ_0 looks) (PP_1 (IN_1 on) (NP_2 (NN_3 dirt))))) (DOT_0 .)))