阅读理解。 Almost everyone likes dogs, and almost everyone likes to read about dogs. I have a friend. He has a big police dog with the name Jack. Police dogs are very clever. Every Sunday afternoon my friend takes Jack for a long walk in the park. Jack likes these long walks very much. One Sunday afternoon a young man came to visit my friend. He stayed a long time. He talked and talked. Soon it was time for my friend to take Jack for a walk. But the visitor still stayed. Jack became much worried. He walked around the room several times and then sat down in front of the visitor and looked at him. But the visitor paid no attention to Jack. He went on talking. At last Jack got angry. He went out of the room and came back a few minutes later. He sat down again in front of the visitor, but this time he took the visitor's cap in his mouth. 1. The young visitor stayed a long time in my friend's house, didn't he? [     ] A. Yes, he was. B. Yes, he did. C. No, he wasn't. D. No, he didn't. 2. Jack became worried because ______. [     ] A. he wanted to go out for a walk B. he wanted to play with him C. he didn't know the young man D. he wanted to eat something 3. Jack sat down in front of the visitor because he wanted . [     ] A. the visitor to talk with him B. to join the talk C. to show the visitor how clever he was D. the visitor to leave the house soon 4. The visitor went on talking and ______. [     ] A. he paid no attention to his cap B. he didn't like Jack C. he paid no attention to Jack D. he didn't know that his cap was taken away by Jack 5. At last Jack took ______ in his mouth. [     ] A. food B. nothing C. the visitor's cap D. the visitor's bag