a white dog is running behind a black dog on a paved path by some grass.
Some dogs are running.
A white dog and a black dog are a small group that could be defined as some dogs, which are running.
exists e1 s1 s2 s3 x1 x2 x3 x4.(by(e1,x4) & n_grass(x4) & on(e1,x3) & n_path(x3) & a_paved(s3) & Theme(s3,x3) & behind(e1,x2) & n_dog(x2) & a_black(s2) & Theme(s2,x2) & Actor(e1,x1) & v_run(e1) & n_dog(x1) & a_white(s1) & Theme(s1,x1))
exists e1 x1.(Actor(e1,x1) & v_run(e1) & n_dog(x1))