A construction worker is working on the side of a bridge.
A construction worker is working at a computer.
He could not be on a computer if he were on the side of a bridge because there are not computers in that location.
exists e1 x1 x2 x3 x4.(n_side(x3) & on(e1,x3) & of(x3,x4) & n_bridge(x4) & Actor(e1,x1) & v_work(e1) & n_worker(x1) & of(x1,x2) & n_construction(x2))
exists e1 x1 x2 x3.(at(e1,x3) & n_computer(x3) & Actor(e1,x1) & v_work(e1) & n_worker(x1) & of(x1,x2) & n_construction(x2))