Bob was a gardener and he had no work for a few months. One day he went out to look for a job. While he was walking in the street, he saw a poster at the gate of a big restaurant. It said the restaurant needed to hire  a man who could grow flowers and trees well. Bob was so pleased that he went straight to answer it. There Bob was told to go back and get his old working clothes to the office. Bob did so. The boss looked over his working clothes carefully and then decided to let Bob have the job. Bob asked the boss why his working clothes were so important. The boss answered with a smile, "Oh, young man, your working clothes are all with patches  on the knees. You know, I have dismissed  two men these days. They had working clothes with patches on the buttocks . They were too lazy." Bob's new job was  _  .
to wash dishes to clean the restaurant to cook dishes to grow flowers and trees