A man saws through a piece of wood to repair a fence.
The fence needs repairing due to rust.
Just because a fence is being repaired doesn't imply due to rust.
exists e1 p1 x1 x2 x3.(through(e1,x2) & Topic(x2,p1) & exists e2 x4.(Theme(e2,x4) & Actor(e2,x2) & v_repair(e2) & n_fence(x4)) & of(x2,x3) & n_wood(x3) & n_piece(x2) & Actor(e1,x1) & v_saw(e1) & n_man(x1))
exists e1 p1 s1 x1 x2 x3.(n_fence(x1) & Theme(e1,x2) & Actor(e1,x1) & v_need(e1) & Topic(s1,p1) & Actor(s1,x3) & a_due(s1) & exists e2.(Actor(e2,x3) & v_rust(e2)) & (x2 = x3) & n_repair(x2))