It was were gravel out maybe clouds as back higher .
(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 It)) (VP_4 (VBD_1 was) (VP_2 (ATVP_4 (ATVP_3 (ATVP_4 (VBD_0 were) (ADJP_0 (JJ_1 gravel) (PP_1 (IN_1 out)))) (ADVP_0 (RB_0 maybe))) (NP_4 (NNS_1 clouds))) (PP_2 (IN_0 as) (NP_6 (RB_1 back) (JJR_0 higher)))))) (DOT_0 .)))