Two dogs play in field of snow
The dogs are rolling in sand.
Dogs can't be in sand and snow at the same time.
exists e1 x1 x2 x3.(in(e1,x2) & of(x2,x3) & n_snow(x3) & n_field(x2) & Actor(e1,x1) & v_play(e1) & n_dog(x1) & card_eq_2(x1))
exists e1 x1 x2.(n_dog(x1) & in(e1,x2) & n_sand(x2) & Actor(e1,x1) & v_roll(e1))