A light brown dog is chasing after a ball.
The dog is sleeping under a tree.
dog that is sleeping can not be chasing ball at the same time.
exists e1 s1 s2 x1 x2.(after(e1,x2) & n_ball(x2) & Actor(e1,x1) & v_chase(e1) & n_dog(x1) & a_brown(s2) & Theme(s2,x1) & a_light(s1) & Theme(s1,x1))
exists e1 x1 x2.(n_dog(x1) & under(e1,x2) & n_tree(x2) & Actor(e1,x1) & v_sleep(e1))