The workers are surrounding a hole with a bucket.
The workers are riding in a truck.
surrounding a hole implies that it's in the ground, which you couldn't be standing on if you're riding in a truck
exists e1 x1 x2 x3.(n_worker(x1) & Theme(e1,x2) & Actor(e1,x1) & v_surround(e1) & with(x2,x3) & n_bucket(x3) & n_hole(x2))
exists e1 x1 x2.(n_worker(x1) & in(e1,x2) & n_truck(x2) & Actor(e1,x1) & v_ride(e1))