City workers are doing maintenance on a train track.
City workers are repairing a road.
Although both of the city workers are busy, one of the groups is working on the train track while the other group is repairing a road. These are two seperate jobs.
exists e1 x1 x2 x3 x4 x5.(on(e1,x4) & n_track(x4) & of(x4,x5) & n_train(x5) & Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & n_maintenance(x3) & n_worker(x1) & (x1 = x2) & ne_geo_city(x2))
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_repair(e1) & n_road(x3) & n_worker(x1) & (x1 = x2) & ne_geo_city(x2))