Two black dogs playing tug-of-war.
Two dogs take turns rolling over onto their backs
playing tug-of-war is not rolling over.
exists e1 s1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_play(e1) & n_tug-of-war(x3) & (x1 = x2) & n_dog(x1) & a_black(s1) & Theme(s1,x1) & card_eq_2(x1))
exists e2 e1 s1 x1 x2 x3 x4.(onto(e2,x4) & n_back(x4) & of(x4,x1) & n_thing(x1) & Theme(e2,x2) & Actor(e2,x1) & v_take(e2) & a_over(s1) & Manner(e1,s1) & Actor(e1,x3) & v_roll(e1) & (x2 = x3) & n_turn(x2) & n_dog(x1) & card_eq_2(x1))