four children lay on a tube.
The tube is from a large truck.
just because children lay on tube doesn't mean that the tube is from a large truck.
exists e1 x1 x2.(on(e1,x2) & n_tube(x2) & Actor(e1,x1) & v_lay(e1) & n_child(x1) & card_eq_4(x1))
exists p1 x1.(n_tube(x1) & exists s1 x2.(from(x1,x2) & n_truck(x2) & a_large(s1) & Theme(s1,x2)))