A group of motorcyclist are ridding through the streets.
The streets were crowded with motorcyclists.
Group of motorcyclist does not necessarily mean streets were crowded with motorcyclists.
exists e1 x1 x2 x3.(n_street(x3) & through(e1,x3) & Actor(e1,x1) & v_rid(e1) & of(x1,x2) & n_motorcyclist(x2) & n_group(x1))
exists e1 x1 x2.(n_street(x1) & with(e1,x2) & n_motorcyclist(x2) & Theme(e1,x1) & v_crowd(e1))