A mountain biker in midair biking while surrounded by grass and trees.
A mountain biker is doing a backflip.
A biker can only make backflip on mountains
exists s1 x1 x2 x3 x4 x5 x6 x7 x8.(a_topic(x1) & in(x1,x3) & by(s1,x6) & subset_of(x8,x6) & n_tree(x8) & subset_of(x7,x6) & n_grass(x7) & Theme(s1,x5) & a_surround(s1) & (x3 = x5) & n_biking(x3) & of(x3,x4) & n_midair(x4) & n_biker(x1) & of(x1,x2) & n_mountain(x2))
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & n_backflip(x3) & n_biker(x1) & of(x1,x2) & n_mountain(x2))