Vendors serve food on the street.
Vendors serving food at a festival
Vendors serving food on the street does not indicate a festival.
exists e1 x1 x2 x3.(n_street(x3) & on(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_serve(e1) & n_food(x2) & n_vendor(x1))
exists e1 x1 x2 x3 x4.(a_topic(x1) & at(e1,x4) & n_festival(x4) & Theme(e1,x3) & Actor(e1,x2) & v_serve(e1) & n_food(x3) & (x1 = x2) & n_vendor(x1))