There are four people dressed in orange clothes walking down the street.
Some inmates are cleaning up the litter.
Just because they are wearing orange does not mean they are inmates, and walking down the street does not imply that they are cleaning up litter.
exists p1 x1 x7.(n_street(x7) & exists e1 e2 x2 x3 x4 x5 x6.((x1 = x2) & in(e1,x4) & down(e2,x7) & Actor(e2,x6) & v_walk(e2) & (x4 = x6) & n_clothes(x4) & of(x4,x5) & n_orange(x5) & Theme(e1,x3) & v_dress(e1) & (x2 = x3) & n_people(x2) & card_eq_4(x2)))
exists e1 s1 x1 x2.(n_litter(x2) & a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_clean(e1) & n_inmate(x1))