根据对话内容，在空白处写出恰当的句子，使句子连贯完整。 John: Uncle Smith, this is John speaking. I'm sorry to call up so late, but may I speak to Jim? Smith: Jim is out. 1_______ John: OK, please. Jim and I applied an adventure (冒险) tour competition on the Internet a week ago. Today I was told that we were accepted. Smith: Oh, that must be dangerous. 2_______ John: Because we want to do sports and something exciting. Smith: You'd better not. 3_______ John: Uncle Smith, don't worry. We can take good care of ourselves. Smith: 4_______ John: Yes. We are ready for it. Smith: Good luck. John: 5_______ Smith: OK. I'll tell him to call you back later.