题目内容
听力原文：W: Hi, Larry, are you waiting to see Professor Johnson, too？
M: Yeah, since I got one of the five highest grades in her managerial economies class, she asked me if I'd be interested in working as her assistant next semester. I'm here now for my interview.
W: Oh, yeah, I know all about that job. I did it two years ago.
M: Really？ Did you like it？
W: I think it was the best job I've had at school. It paid eight dollars an hour, which was three dollars an hour more than I got working at the school post office the year before.
M: Wow! That is a good salary. What did you do？
W: I was in charge of grading all the problem sets that were assigned as home work. I never had trouble doing it, and of course, Prof. Johnston was always available to help me if I had any questions.
M: I think I'd enjoy doing that sort of work. It would be a very good experience for someone thinking about becoming a teacher.
W: Absolutely. You aim learn how to use the computer data base, because the records are kept on it, and building up your computer skills is geed preparation for lots of jobs.
M: The job sounds great, but I am a little worried about bow much time it might take？
W: It's all pretty reasonable. It never took me more than five hours a week to do all the grading mad then another thirty to forty minutes to record the grades on the computer.
M: That sounds manageable. I guess you can do the work when it fits into your own schedule, too, can't you？
W: Oh, yeah, you can do the grading in your room or in the library. You just need to get each set back for the next class, but that means you always have at least two days and sometimes four.
M: It sounds great.
W: Good luck with your interview.
(27)
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Section A
Directions: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer.
听力原文：W: I see a new bookstore has just opened on Main Street.
M: It may be a new store. But the books are anything but new.
Q: What does the man mean？
(12)
听力原文：W: Hello？
M: Hi, Amy. This is Bill Johns.
W: Oh hi, Bill. You weren't in engineering class today, weren't you？
M: I have the flu. I was wondering if you could tell me what went on.
W: Actually we had an interesting class. Dr. Collin talked about a new type of fuel.
M: Oh, yeah？
W: Uhhum, It's called Dimethyl ether or DME.
M: Oh, I remember reading something about DME. It's mostly used in spray cans,, right？
W: Right, DME doesn't destroy the ozone, so it is environmental friendly.
M: But doesn't DME pollute the air if it's burned in an engine？
W: Dr. Collin said something about its exhaust being dean, that it doesn't re lease as much pollutant as diesel fuel. And he mentioned something about DME being more efficient than other alternative fuels.
M: When will it replace diesel fuel？
W: Not for a while. It's not economical to massproduce.
M: Well, thanks for the information. I guess I won't need to borrow your notes.
W: Well, maybe you should look at them. We are having a test next week.
M: Okay, could you give them to Mike Andrews？ I think he is in your psychology class. He is my roommate.
W: Sure. I hope you're feeling better soon.
M: Thanks. Me too. Bye!
W: Bye!
(20)
When the acidity insists on dropping, many creatures in the lakes and ponds will become affected.
ACID RAIN: What's the Solution？
One of the wildest regions in the U.S., far from civilization, is the Adirondack area of northern New York State. For years this isolated spot has had the reputation of being one of best fishing spots in the U.S.
As a boy 30 years ago, Bill Marleau first through the Adirondack wilderness near his small cabin on Woods Lake. Thousands of sportsmen have stayed at his father's lodge nearby.
But now Bill's 134 hectares (335 acres) of lakefront land have only scenic value. Gone are those huge trout that used to swim in the turbulent, nutrientrich water a short distance from his doorstep. Gone from the cool nights are the sounds of thousands of frogs and toads.
And gone are the birds that once fed on those water creatures.
Occasionally Bill sees a lone fisherman fruitlessly cast his bait into the empty waters of old lake. "I just don't have the heart to tell," he said. "This old lake's dead. It was killed years ago by acid rain." What is acid rain？
Acid rain is a popular term for precipitation in the form. of rain, sleet, snow or hail that is more acidic than normal. Acid rain is produced when atmospheric moisture combines with pollutants from power plants, factories and automobiles.
When fossil fuels such as coal and oil are burned, sulfur dioxide and nitrogen dioxide are produced. These two gases react with the water and oxygen in the atmosphere to form. droplets of weak sulfur and nitric acid.
Carried by prevailing winds and weather conditions, clouds containing these droplets travel hundreds, sometimes thousands, of kilometers from the source of the pollutants. Recently scientists found that acid rain now affects huge areas of the North Hemisphere.
Power plants and factories in the heavily industrialized regions of Ohio and Indiana are believed to be the source of the acid rain that killed Woods Lake along with hundreds of others in New York State and eastern Canada. Acid haze over Alaska is believed to come all the way from Japan. And precipitation as acid as vinegar that falls on Scotland and Scandinavia probably originates in England.
How Acidity Is Measured
Scientists measure the acidity of rain in pH units. A pH scale from 0 to 14 is used. Depending upon its chemical composition, a solution is either acidic, alkaline (basic), or neutral. Distilled water, which has a pH of 7, is neutral. Substance with pH values less than 7 are acidic, while those over 7 are alkaline.
Normal rain water with a pH of 5.6 is slightly acidic. But after reacting with industrial pollutants, particularly sulfur dioxide, the pH of rain quickly drops.
When acid rain falls to Earth, much of it ends up in lakes and ponds. In addition to failing directly into a lake, acid rains runs off land into streams and rivers that eventually flow into lakes and ponds. Once acid rain gets into them, its effects can be deadly.
Studies started in 1975 in the Adirondacks indicate that salamanders and frogs are the first to die when the pH is lowered. Normally the pH of a lake is 8,0 slightly alkaline. When the pH drops to 7, the eggs of salamanders and frogs fail to hatch. At pH 6.6 snails begin to die.
Bacteria that decompose leaf matter die too, and the leaf matter collects on the lake bottom. As the acidity continues to drop, ail the major food chains in the lake become affected. In time all the fish die.
Eventually primitive, oxygenconsuming plants nearly choke out all other aquatic greenery. Algae and fungal growth that thrive in an acidic environment move in and cover the entire bottom of the now destroyed lake.
Looking like blue vinegar, the lake is now an entirely changed ecosystem. It contains no life expect the fungal and algal growth and a few surfacedwelling water bugs.
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