听力原文: When you take a walk in any of the cities in the West, you often see a lot of people walking 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 have changed. In the old days people used to train dogs to protect themselves against attacks by other beasts. And later they came to realize that a dog was not only useful for protection but willing to obey his master. For example, when people used dogs for hunting, the dogs would not eat what was caught without permission. 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 most important reason is for companionship. For a child, a dog is his best friend when he has no friends to play with. For young couples, a dog is their 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 to friendship.
(37)
A.For protection against other dogs.
B.For protection against other animals.
C.Just for fun.
D.For the purpose of guarding the house.
第2题
A.机架式交换机、带扩展槽固定配置式交换机、不带扩展槽固定配置式交换机和可堆叠交换机
B.第2层交换机、第3层交换机、第4层交换机和第7层交换机
C.桌面交换机、工作组级交换机、部门级交换机和企业级交换机
D.以太网交换机、快速以太网交换机、千兆位以太网交换机、FDDI交换机和ATM交换机
第3题
A.桌面交换机、工作组级交换机、部门级交换机和企业级交换机
B.以太网交换机、快速以太网交换机、千兆位以太网交换机、FDDI交换机和ATM交换机
C.机架式交换机、带扩展槽固定配置式交换机、不带扩展槽固定配置式交换机和可堆叠交换机
D.第2层交换机、第3层交换机、第4层交换机和第7层交换机
第5题
连接以太网交换机的模式有两种:级连和堆叠,其中堆叠模式(37)。以太网交换机划分VLAN有多种方法,(38)不包括在内。在用户配置VLAN时,应从(39)开始。
A.仅有菊花链堆叠
B.既有菊花链堆叠,又有矩阵堆叠
C.仅有矩阵堆叠
D.并联堆叠
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