题目内容
A．Fort Dearborn was built in 1833 in the place that would become Chicago.B．Chicago did
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A．It is inconvenient to take the baggage onto it.B．It is difficult to spare the room f
M: Well, yes, it's very exciting. For a long time we'd 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: Let's call it a hidden biosphere, and it's 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. We've found a very special organism. Let's 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 that's completely different from humans'. That's to say. they could not survive in our environment. So we really don't need to worry about these bacteria causing illness in people.
(20)
听力原文： A beetle invasion in the United States has killed at least twenty million ash trees. The invasion of the emerald ash borer was first discovered near Detroit, Michigan, in 2002. Experts believe the small green insects arrived in the 1990's in shipments of goods from China.
The emerald ash borer has destroyed trees in the Midwest and as Far East in the United States as Maryland. The insects have also spread as far north as Ontario, Canada.
Ash trees can resist many diseases. But they cannot resist the emerald ash borer. It lays eggs on the bark. The young larva drill into and feed on the inner bark. This harms the ability of the tree to transport water and nutrition.
In some places, farmers .are using "detection trees". They have an area where bark has been cut away. The area circles the tree. The process weakens the tree. It makes them easier targets for borers, and shows if the insects are nearby.
Efforts to stop the spread of the emerald ash borer include cutting down affected trees. There are worries that the ash tree might disappear unless the invasion is controlled. To prepare for such a possibility, a government laboratory is asking people to send in the seeds from ash trees. It examines and X-rays the seeds to make sure that there are no living borer fertilized eggs. Only the best seeds are remained and then sent for storage in a seed bank. There, they are dried and frozen. Should the seeds ever be needed, the hope is that scientists might someday develop an ash tree that could resist the little green attackers.
(30)
听力原文：M: I knew Mary played the piano．but I didn't know she played the guitar．
W: Neither did I．It seems she just picked it up on her own，over the summer．She does have an artistic talent．
Q: What can we learn about Mary from the conversation？
(15)
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