a woman stands behind a display of food.
Nobody is standing.
There cannot be both a woman and nobody in a space.
exists e1 x1 x2 x3.(behind(e1,x2) & of(x2,x3) & n_food(x3) & n_display(x2) & Actor(e1,x1) & v_stand(e1) & n_woman(x1))
-exists e1 x1.(Actor(e1,x1) & v_stand(e1) & n_person(x1))