A dog is running towards a ball.
The dog is chasing a blue ball.
Balls come in many colors; we can't infer that they are always blue.
exists e1 x1 x2.(towards(e1,x2) & n_ball(x2) & Actor(e1,x1) & v_run(e1) & n_dog(x1))
exists e1 s1 x1 x2.(n_dog(x1) & Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_ball(x2) & a_blue(s1) & Theme(s1,x2))