Sheepdogs are very important to farmers. Sheepdogs help farmers to find their __51__ and bring them back to the farm. Mike, a farmer from a __52__, has a very clever and honest sheepdog __53__ Bobby. He has built a little but __54__ house for Bobby and he regards the dog __55__ a family member. He often says. "Bobby is the best dog in the world. He works hard and __56__ my sheep very well." If the dog house is __57__. Mike knows Bobby must be with his sheep. Mike __58__ with Bobby through whistles(口哨)。Bobby can understand many different instructions from those __59__. And Bobby can also __60__ himself by barking(狗叫) or doing other actions. Mike loves Bobby very much. They are getting on well with each other