a group of dogs playing
The dogs running and playing.
Dogs can play by rolling around or tug-of-war, in this case it was running.
exists e1 x1 x2 x3.(a_topic(x1) & Actor(e1,x3) & v_play(e1) & (x1 = x3) & of(x1,x2) & n_dog(x2) & n_group(x1))
exists e1 e2 x1.(n_dog(x1) & Actor(e2,x1) & v_play(e2) & Actor(e1,x1) & v_run(e1))