A group of motorcyclists riding down the street.
People are riding bicycles.
One group is riding motorcycles, then the second group are on bicycles.
exists e1 x1 x2 x3 x4.(n_street(x4) & a_topic(x1) & down(e1,x4) & Actor(e1,x3) & v_ride(e1) & (x1 = x3) & of(x1,x2) & n_motorcyclist(x2) & n_group(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bicycle(x2) & n_people(x1))