A red ambulance drives down the street as two people look on.
the ambulance is carrying a passenger
ambulance driving down the street does not imply it is carrying a passanger
exists e1 p1 s1 x1 x2 x3 x4.(n_street(x3) & exists s2.(Theme(s2,x1) & a_on(s2)) & Topic(e1,p1) & Actor(e1,x1) & v_look(e1) & as(x1,x4) & n_people(x4) & card_eq_2(x4) & down(x1,x3) & n_drive(x1) & of(x1,x2) & n_ambulance(x2) & a_red(s1) & Theme(s1,x1))
exists e1 x1 x2.(n_ambulance(x1) & Theme(e1,x2) & Actor(e1,x1) & v_carry(e1) & n_passenger(x2))