Several people wearing orange vests are walking along the railroad tracks.
The people are by the tracks.
Several people are people and walking along the railroad tracks is another form of being by the tracks.
exists e2 e1 s1 x1 x2 x3 x4 x5 x6.(n_track(x5) & of(x5,x6) & n_railroad(x6) & along(e2,x5) & Actor(e2,x1) & v_walk(e2) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & n_vest(x3) & of(x3,x4) & n_orange(x4) & (x1 = x2) & n_people(x1) & a_several(s1) & Theme(s1,x1))
exists p1 x1 x2.(n_track(x2) & n_people(x1) & by(x1,x2))