people are looking at the antique cars, and the police officer is taking pictures.
People are observing old cars while a cop photographs them
People are observing old cars while a cop photographs them refers to people and police officer
exists e2 e1 s1 x1 x2 x3 x4 x5.(n_officer(x3) & of(x3,x4) & n_police(x4) & n_car(x2) & a_antique(s1) & Theme(s1,x2) & Theme(e2,x5) & Actor(e2,x3) & v_take(e2) & n_picture(x5) & at(e1,x2) & Actor(e1,x1) & v_look(e1) & n_people(x1))
exists e1 p1 s1 x1 x2.(exists e2 x3.(Theme(e2,x1) & Actor(e2,x3) & v_photograph(e2) & n_cop(x3)) & n_thing(x1) & while(e1,p1) & Theme(e1,x2) & Actor(e1,x1) & v_observe(e1) & n_car(x2) & a_old(s1) & Theme(s1,x2) & n_people(x1))