When I was young, I spent my summer vacations on my grandparents' farm. The summer that I graduated from college, I 56 my grandparents once again. When I arrived,I discovered that there was a family 57 in progress. Grandpa's dog and hunting partner, Rusty, had taken on a very bad 58 in his old age. He had begun 59 into the chicken coop (鸡笼) and eating eggs. In the eyes of the local farmers, 60 dogs started stealing eggs, there was no 61 to cure them. They knew there was only one thing to be done 62 such a dog-you had to shoot it and the sooner the 63 . Rusty and Grandpa were old friends. Grandpa certainly didn't to shoot Rusty,but he knew it needed to be done. The 66egg money" was Grandma's private income, so you can imagine 65 she felt about the problem. 66 the inexperienced confidence of youth, I told Grandpa that I thought I could"cure"the egg-stealing dog. I wanted to at least have a 67 to save Rusty's life, and save Grandpa from the sadness of 68 Rusty. The next morning, I broke open six fiesh eggs and put them in Rusty's bowl 69 at the door to the chicken coop. Rusty came 70 and noticed the eggs. He quickly 71 the eggs and happily walked off for his nap (打盹). The following morning I did the 72 thing.I put the eggs a few feet away from the chicken coop, toward the back door of the farmhouse 73 Grandma usually fed Rusty. The next day I again moved the bowl closer to the house, and added some dog food to the eggs. Every day I moved the bowl closer to the back door, mixing more dog food and 74 eggs. By the time the bowl reached the door, it was all dog food and no eggs. Rusty had again become 75 to looking for his food at the back door of the house, and never again went into the chicken coop.65.A.how B.when C.what D.which