A group of dogs racing.
A group of greyhounds race as the gamblers scream.
Not all dogs are greyhounds.
exists e1 x1 x2 x3.(a_topic(x1) & Actor(e1,x3) & v_race(e1) & (x1 = x3) & of(x1,x2) & n_dog(x2) & n_group(x1))
exists e1 x1 x2 x3 x4.(n_gambler(x4) & Actor(e1,x1) & v_scream(e1) & as(x1,x4) & of(x1,x2) & n_race(x2) & of(x2,x3) & n_greyhound(x3) & n_group(x1))