Two men are looking at a piece of machinery outdoors.
Two machinists repair a piece of machinery.
Just because two men are looking at machinery does not mean that they are machinists.  And just because they are looking a piece of machinery, does not mean that they are repairing it.
exists e1 x1 x2 x3 x4.(at(e1,x2) & of(x2,x3) & n_outdoors(x3) & of(x3,x4) & n_machinery(x4) & n_piece(x2) & Actor(e1,x1) & v_look(e1) & n_man(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_repair(e1) & of(x2,x3) & n_machinery(x3) & n_piece(x2) & n_machinist(x1) & card_eq_2(x1))