Men taking a break from working on a piece of yellow industrial equipment.
Men sitting on a piece of industrial equipment during their break.
If the men are taking a break from working, they are engaged in some activity other than working, such as sitting, during their break. If they are "on" something then they are most likely sitting on that something.
exists e2 e1 s1 s2 x1 x2 x3 x4 x5.(a_topic(x1) & from(e1,e2) & on(e2,x4) & of(x4,x5) & n_equipment(x5) & a_industrial(s2) & Theme(s2,x5) & a_yellow(s1) & Theme(s1,x5) & n_piece(x4) & Actor(e2,x2) & v_work(e2) & Theme(e1,x3) & Actor(e1,x2) & v_take(e1) & n_break(x3) & (x1 = x2) & n_man(x1))
exists e1 s1 x1 x2 x3 x4 x5.(a_topic(x1) & on(e1,x3) & during(x3,x5) & n_break(x5) & of(x5,x1) & n_thing(x1) & of(x3,x4) & n_equipment(x4) & a_industrial(s1) & Theme(s1,x4) & n_piece(x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_man(x1))