A dog zips along the beach.
A dog is chasing a ball on the beach.
You cannot infer that a dog is chasing a ball just from "a dog zips".
exists e1 x1 x2.(n_beach(x2) & along(e1,x2) & Actor(e1,x1) & v_zip(e1) & n_dog(x1))
exists e1 x1 x2 x3.(n_beach(x3) & on(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_ball(x2) & n_dog(x1))