六级听力练习IV录音文字.doc

Section A Directions: In this section, you will hear two long conversations.At the end of each conversation, you will hear some questions. Both the conversation and the questions will be spoken only once.After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D).Then mark the corresponding letter on Answer Sheet 1with a single line through the centre. Conversation One W: Todays guest on Science Update is David Brown. Dr. Brown, you and your team have found bacteria far below the Earths surface. You must be thrilled about your discovery. M: Well, yes, its very exciting. For a long time wed suspected the presence of such organisms, but we lacked substantial evidence. W: How did you confirm the existence of the bacteria? M: Well, technology helped. Our drilling techniques have improved significantly, and so the risk that surface bacteria could be mistaken for those found at much greater depth was reduced. With the new techniques, we could get much deeper into the Earth. W: How far down did you actually get? M: In one case, about three kilometers. We were surprised, I must tell you, that there were organisms that far down. W: You know, it sounds like fiction, something like a lost world. M: Lets call it a hidden biosphere, and its probably a very extensive one. The mass of the living organisms below the surface may be equal in size to the mass of the surface bacteria. W: Have you found any unique life-forms? M: Yes. Weve found a very special organism. Lets call it Type-A bacterium. It can live and grow only where there is no oxygen. W: Is there any danger of these bacteria infecting people when you bring them to the surface? M: These bacteria were adapted to an environment thats completely different from humans. Thats to say, they could not survive in our environment. So we really dont need to worry about these bacteria causing illness in people. Questions 1 to 4 are based on the conversation you have just heard. 1. What