1 The friend has a large police dog called jack.
2 But the visitor paid no attention to the dog.
3 最后，杰克再也不能忍受。
4 to walk
5 B
1 用过去分词做定语，修饰a large dog：The friend has a large police dog called jack.
2 考查词组：pay attention to注意：But the visitor paid no attention to the dog.
3 put up with忍受，not…any more不再，最后，杰克再也不能忍受。
4 从第一段的句子：Every Sunday afternoon my friend takes Jack for a long walk in the park, 可知答案是to walk
5 从故事的描述看，这是一只聪明的狗。选B