Workers in hard hats at a railroad tracks construction site.
Some workers in yellow helmets are working.
Workers in hard hats may not necessarily be working, they could be on break.
exists e1 s1 x1 x2 x3 x4 x5.(Theme(e1,x4) & Actor(e1,x1) & v_track(e1) & n_site(x4) & of(x4,x5) & n_construction(x5) & in(x1,x2) & at(x2,x3) & n_railroad(x3) & n_hat(x2) & a_hard(s1) & Theme(s1,x2) & n_worker(x1))
exists e1 s1 x1 x2.(Actor(e1,x1) & v_work(e1) & in(x1,x2) & n_helmet(x2) & a_yellow(s1) & Theme(s1,x2) & n_worker(x1))