A dog running on the beach.
A dog goes after an unseen frisbee.
Not all dogs running on the beach are chasing a frisbee.
exists e1 x1 x2 x3.(n_beach(x3) & a_topic(x1) & on(e1,x3) & Actor(e1,x2) & v_run(e1) & (x1 = x2) & n_dog(x1))
exists e1 s1 x1 x2.(after(e1,x2) & n_frisbee(x2) & a_unseen(s1) & Theme(s1,x2) & Actor(e1,x1) & v_go(e1) & n_dog(x1))