A man in an orange vest and yellow hard hat looks on as a yellow vehicle lays track.
people replace old track
One man does not mean there are multiple people. Laying track does not imply you are replacing old track.
exists e1 e2 s1 s2 s3 x1 x2 x3 x4 x5 x6 x7 x8.(r_on(e1) & as(e1,x6) & Theme(e2,x8) & Actor(e2,x7) & v_lay(e2) & n_track(x8) & (x6 = x7) & n_vehicle(x6) & a_yellow(s3) & Theme(s3,x6) & Actor(e1,x1) & v_look(e1) & in(x1,x2) & n_hat(x4) & a_hard(s2) & Theme(s2,x4) & a_yellow(s1) & Theme(s1,x4) & n_vest(x3) & of(x3,x5) & n_orange(x5) & subset_of(x4,x2) & subset_of(x3,x2) & n_man(x1))
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_replace(e1) & n_track(x2) & a_old(s1) & Theme(s1,x2) & n_people(x1))