Men are working by a cement mixer.
Guys working near a cement mixer.
Men and guys are terms that mean the same thing in a broad sense.
exists e1 x1 x2 x3.(by(e1,x2) & n_mixer(x2) & of(x2,x3) & n_cement(x3) & Actor(e1,x1) & v_work(e1) & n_man(x1))
exists e1 x1 x2 x3.(near(e1,x2) & n_mixer(x2) & of(x2,x3) & n_cement(x3) & Actor(e1,x1) & v_work(e1) & n_guy(x1))