A young male boy is sitting backwards on a gray mule in the dessert.
The mule is purple.
The mule is either gray or purple.
exists p1 s1 x1 x2 x5.(n_dessert(x5) & exists e1 s2 x3 x4.((x1 = x3) & on(x3,x4) & in(x4,x5) & n_mule(x4) & a_gray(s2) & Theme(s2,x4) & n_backward(x3) & Actor(e1,x3) & v_sit(e1)) & n_boy(x1) & of(x1,x2) & n_male(x2) & a_young(s1) & Theme(s1,x1))
exists s1 x1.(n_mule(x1) & Theme(s1,x1) & a_purple(s1))