A dog plays in the sand with a ball.
A dog returns a ball that was thrown.
The dog plays with a ball but it's not necessarily true that the dog returns a ball that was thrown.
exists e1 x1 x2 x3.(n_sand(x2) & with(e1,x3) & n_ball(x3) & in(e1,x2) & Actor(e1,x1) & v_play(e1) & n_dog(x1))
exists e2 e1 x1 x2 x3.(n_thing(e2) & Theme(e2,x2) & Actor(e2,x1) & v_return(e2) & Theme(e1,x3) & v_throw(e1) & (x2 = x3) & n_ball(x2) & n_dog(x1))