Two children are sitting while one is standing over them.
There are no children.
If there are no children, then none would be sitting or standing.
exists e1 p1 x1.(exists e2 x2.(over(e2,x1) & Actor(e2,x2) & v_stand(e2) & n_thing(x2) & card_eq_1(x2)) & n_thing(x1) & while(e1,p1) & Actor(e1,x1) & v_sit(e1) & n_child(x1) & card_eq_2(x1))
exists p1 x1.-exists x2.((x1 = x2) & n_child(x2))