The four children are playing with a ball outside a building.
The children have no toys.
The four children playing with a ball outside a building means they cannot be without toys as ball can be considered as a type of toy.
exists e1 x1 x2 x3.(n_child(x1) & card_eq_4(x1) & with(e1,x2) & outside(x2,x3) & n_building(x3) & n_ball(x2) & Actor(e1,x1) & v_play(e1))
exists x1.(n_child(x1) & -exists e1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & n_toy(x2)))