People, some in uniform, milling about on a street.
There are some police officers in uniform milling with the other people on the street
People in uniforms are not necessarily police officers.
exists e1 s1 x1 x2 x3 x4.(a_about(s1) & Manner(e1,s1) & on(e1,x4) & n_street(x4) & Actor(e1,x1) & v_mill(e1) & rel(x1,x2) & in(x2,x3) & n_uniform(x3) & n_thing(x2) & n_people(x1))
exists p1 s1 x1 x2 x3 x4.(n_street(x4) & -(x3 = x3) & n_people(x3) & with(p1,x3) & on(x3,x4) & in(p1,x2) & n_milling(x2) & a_uniform(s1) & Theme(s1,x2) & exists x5 x6.((x1 = x5) & n_officer(x5) & of(x5,x6) & n_police(x6)))