听力题 W: Hi, Paul, are you ready for your Speech Club presentation this evening? M: Yeah, I''m going to discuss robots. W: Robots? You mean those machines that walk and talk like in the movies? M: No, industrial robots like those used in the automobile and electronic industries. W: I saw an article a about kind of robot the other day. They were pictures of robots welding cars, but they certainly didn''t look the way I thought robots should look. M: The robots we usually imagine are made up in science fiction. In industry, robots are designed to do a specific set of operations, such as welding car frames. They are rarely built to resemble humans. W: Actually, all they need is a kind of brain to give signals, and a mechanism, such as an arm, to carry out instructions, right? M: Right. Tiny computers become the brain of these robots. The computer sends signals, in the form of electronic impulses, and moves an arm and a claw. The claw is the hand that does particular kinds of work. W: Ok. But we''ve had machines on assembly lines doing work for people for years. That''s what started the industrial revolution, remember? M: But each of those machines can only perform a single operation and it takes months to modify them. The new industrial robots can each do a number of tasks. And it''s easy to reprogram them to perform totally different operations. That''s one reason why they''re becoming so popular. W: They increase productivity too, don''t they? I read that even though they''re still quite expensive, they often cost less per year than a worker doing the same job. I imagine robots will be used more and more. M: Exactly. So now that you know all about the next industrial revolution, you don''t have to come to Speech Club tonight.