Also, if you look at prison movies, sometimes the way that the guards torture the prisoners is to get them to dig a hole, and when the prisoner is finished, they ask him to fill the hole back up and then dig again.
Tamén se pensamos en filmes de cárceres ás veces a forma que teñen  os gardas de torturar os presos é mandarlles cavar un burato e cando o preso remata, mándanlle  reencher o burato e cavalo de novo.