A black dog chasing a brown one.
A brown dog is chasing a black one.
A black dog cannot be chasing a brown dog at the same time.
exists e1 s1 s2 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_chase(e1) & n_thing(x3) & card_eq_1(x3) & a_brown(s2) & Theme(s2,x3) & (x1 = x2) & n_dog(x1) & a_black(s1) & Theme(s1,x1))
exists e1 s1 s2 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_thing(x2) & card_eq_1(x2) & a_black(s2) & Theme(s2,x2) & n_dog(x1) & a_brown(s1) & Theme(s1,x1))