A backhoe is digging a trench outside of a building.
A trench is being dug.
Only the backhoe is digging the trench.
exists e1 x1 x2 x3 x4.(Theme(e1,x2) & Actor(e1,x1) & v_dig(e1) & of(x3,x4) & n_building(x4) & outside(x2,x3) & n_thing(x3) & n_trench(x2) & n_backhoe(x1))
exists p1 x1.(exists x2.((x1 = x2) & n_dug(x2)) & n_trench(x1))