题目内容：
根据下面资料，回答题 提示：蒂姆和哈里正在讨论关于所听到的演讲的问题。哈里认为这次演讲很生动，蒂姆则与其观点相反。蒂姆认为他们找不到人们去从事煤炭行业，将来唯一能利用的能源是原子能，哈里则认为他们能发明许多新的机器代替人工。
Tim: 51
Harry: I thought it was very interesting.
Tim : 52
Harry: Yes, didn't you?
Tim: Certainly not. 53
Harry: So you think you know more than he does.
Tim: Well, take coal for instance.
Harry: 54
Tim: Coal won't become important again.
Harry: Why not?
Tim: It's too dirty. They won't be able to find people to work down coal mines in the ture.
Harry : 55
Tim: Nonsense. The only sort of power they'll use in the future is atomic power.
第（51）题
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