Construction workers building a railroad.
Workers are laying down metal rails for a track.
The construction worker are building a railroad but that that time, they aren't necessarily laying down metal rails for a track.
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_build(e1) & n_railroad(x3) & n_worker(x1) & of(x1,x2) & n_construction(x2))
exists e1 s1 x1 x2 x3 x4.(a_down(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_lay(e1) & for(x2,x4) & n_track(x4) & n_rail(x2) & of(x2,x3) & n_metal(x3) & n_worker(x1))