on surfers , you have to , to .
(ROOT_0 (S_0 (ATS_3 (ATS_1 (ATS_2 (PP_2 (IN_0 on) (NP_4 (NNS_1 surfers))) (COMMA_0 ,)) (NP_0 (PRP_1 you))) (VP_3 (ATVP_3 (ATVP_2 (VBP_0 have) (S_2 (VP_0 (TO_0 to)))) (COMMA_0 ,)) (S_2 (VP_0 (TO_0 to))))) (DOT_0 .)))