A man stands at the passenger door of an emergency vehicle.
A person standing.
A person could be standing at a passenger door.
exists e1 x1 x2 x3 x4 x5.(n_door(x2) & of(x2,x3) & n_passenger(x3) & at(e1,x2) & of(x2,x4) & n_vehicle(x4) & of(x4,x5) & n_emergency(x5) & Actor(e1,x1) & v_stand(e1) & n_man(x1))
exists e1 x1 x2.(a_topic(x1) & Actor(e1,x2) & v_standing(e1) & (x1 = x2) & n_person(x1))