you discovered the surfer Within a tree .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_1 you)) (VP_4 (VBD_0 discovered) (NP_3 (NP_5 (DT_0 the) (NN_2 surfer)) (PP_0 (IN_0 Within) (NP_5 (DT_0 a) (NN_2 tree)))))) (DOT_0 .)))