题目内容
When you take a walk in any of the cities in the West, you can see a lot of people 1.________(walk) with dogs. It is still true that a dog is the most useful and faithful animal in the world, but the reasons why people keep a dog 2._______(change). In the old days people used to train dogs to protect themselves against attacks by other beasts. And 3._______(late) they came 4.________(realize) that a dog was not only useful for protection, 5.________ also willing to obey his master. For example, when people used dogs for hunting, the dogs would not eat what was caught without 6.____(permit). But now people in the city need not protect themselves against attacks of animals. Why do they keep dogs, then? Some people keep dogs to protect themselves from robbery. But the 7.__________(important) reason is for companionship. For a child, 8.__________dog is his best friend when he has no friends to play with. For young couples, a dog is 9.________child when they have no children. For old couples, a dog is also their child when their real children have grown up. So the main reason why people keep dogs has changed from protection 10._______ friendship.