Passage One

　　Questions 57 to 61 are based on the following passage.

　　Electric cars are dirty. In fact, not only are they dirty, they might even be more dirty than their gasoline-powered cousins.

　　People in California love to talk about "zero-emissions vehicles," but people in California seem to be clueless about where electricity comes from. Power plants most all use fire to make it. Aside from the few folks who have their roofs covered with solar cells, we get our electricity from generators. Generators are fueled by something - usually coal, oil, but also by heat generated in nuclear power plants. There are a few wind farms and geothermal plants as well, but by far we get electricity mainly by burning something.examda.com

　　In other words, those "zero-emissions" cars are likely coal-burning cars. It's just the coal is burned somewhere else so it looks clean. It is not. It's as if the California Greens are covering their eyes - "If I can't see it, it's not happening." Gasoline is an incrediblyefficient way to power a vehicle; a gallon of gas has a lot of energy in it. But when you take that gas (or another fuel) and first use it to make electricity, you waste a nice part of that energy, mostly in the form of wasted heat - at the generator, through the transmission lines, etc.

　　A gallon of gas may propel your car 25 miles. But the electricity you get from that gallon of gas won't get you nearly as far - so electric cars burn more fuel than gas-powered ones. If our electricity came mostly from nukes, or geothermal, or hydro, or solar, or wind, then an electric car truly would be clean. But for political, technical, and economic reasons, we don't use much of those energy sources.

　　In addition, electric cars' batteries which are poisonous for a long time will eventually end up in a landfill. And finally, when cars are the polluters, the pollution is spread across all the roads. When it's a power plant, though, all the junk is in one place. Nature is very good at cleaning up when things are not too concentrated, but it takes a lot longer when all the garbage is in one spot.

　　注意：此部分试题请在答题卡2上作答。

　　57. What does "clueless" mean in paragraph 2?

　　A) The California Greens are covering their eyes.

　　B) People in California love to talk about zero-emissions vehicles

　　C) People in California love to have their roofs covered with solar cells

　　D) People there have no idea that so far electricity mainly comes from burning coal, oil, etc.

　　58. According to the passage, why the California Greens hold the idea "If I can't see it, it's not happening."?

　　A) They do not know those clean cars are likely coal-burning cars.

　　B) They do believe that the coal is burned somewhere else so it looks clean.

　　C) They tend to hold that electricity is a nice part of energy.examda.com

　　D) They tend to maintain that gasoline is a good way to run a vehicle.

　　59. The electricity we get from a gallon of gas may make our car run __________.

　　A) not less than 25 miles.

　　B) more than 25 miles.

　　C) no less than 25 miles.

　　D) not more than 25 miles.

　　60. Compared with cars using gas, electric cars __________

　　A) do not burn fuel and more environmental.

　　B) are toxic and it is difficult for nature to clean it up when their batteries are buried in one spot.

　　C) are very good at cleaning up when things are not too concentrated

　　D) are poisonous for a long time and will eventually end up in a landfill.

　　61. It can be inferred from the passage that __________.

　　A) Being green is good and should be encouraged in communications

　　B) Electric cars are not clean in that we get electricity mainly by burning something.

　　C) Zero-emissions vehicles should be chosen to protect our environment.

　　D) Electric cars are now the dominantvehicle compared with gasoline-powered cousins.

　Passage Two

　　Questions 62 to 66 are based on the following passage.

　　Rising global carbon dioxide levels tied to global warming may not be as crucial in determining the composition of plant communities as other, localized climate changes.

　　"Nobody really knows what the increases in carbon dioxide are going to entail in terms of future changes in vegetation types," said Mark Brenner, a University of Florida assistant professor of paleolimnology, the study of ancient lakes. "It looks like climate changes in different areas may be more important than carbon dioxide, at least carbon dioxide by itself," he said.

　　Brenner's research team based their conclusions on an analysis of sediment from two lake bottoms, one in northern Mexico and one in northern Guatemala. The researchers used new techniques that allowed them to analyze only the remains of land plants, specifically their leaf waxes. By measuring the composition of the leaf waxes, the researchers were able to distinguish two broad categories of plants living in these areas -- so-called C3 and C4 plants, which have different photosynthetic(光合作用) processes. Many C4 plants are tropical grasses, while most tropical trees are C3 plants. The researchers analyzed sediments(沉积物) deposited over the last 27,000 years, from the last ice age to the current geological period. Over this period, there was a worldwide, relatively uniform increase in atmospheric carbon dioxide concentrations.

　　Brenner said that if carbon dioxide played the major role in determining plant composition, one would assume that analysis of the sediments would reveal very similar changes in relative abundance of C3 and C4 plants in the two places over the study period. But, in fact, the researchers found that trends in the two types of plants were different at the two locations. The changes were related not with carbon dioxide levels, but with shifts in rainfall. "The result appears to be that climate factors, especially moisture availability, determine whether C4 or C3 plants dominate in an area, not carbon dioxide," Brenner said.

　　Many scientists believe global warming will cause major variation in local climates worldwide, with some wet areas becoming dry and dry areas becoming wet. If that happens, it could have more impact on relative C3 versus C4 plant distribution than the rising carbon dioxide levels.

62. What can be inferred in the first paragraph?

　　A) Climate changes are more important to the composition of plant communities than rising global carbon dioxide.

　　B) Localized climate shifts may not be as crucial as carbon dioxide.

　　C) Nobody knows which one is important.

　　D) Carbon dioxide levels is crucial to the global warming.

　　63. What is Mark Brenner?

　　A) He studies co-author's opinion.

　　B) He is assisting the University of Florida.

　　C) He is an expert in the field of ancient lakes.

　　D) His research team composed of six geologists and geographers.

　　64. According to the third paragraph, which one is NOT true?

　　A) Tropical grasses are usually C4 plants.

　　B) C3 and C4 plants used to live in northern Mexico and Guatemala.

　　C) C3 and C4 plants don't have the same processes.

　　D) Tropical trees are all C3 plants.

　　65. Why, in the 4th paragraph, the researchers found that trends in C3 and C4 plants were different at the two locations?

　　A) The assumption that carbon dioxide played the major role is wrong.

　　B) The carbon dioxide played an important role.

　　C) The moisture availability was different.

　　D) The carbon dioxide level was different.

　　66. What's the main idea of the passage?

　　A) Climates factors determine the plant distribution and composition of plant communities.

　　B) Global warming will cause major variation.

　　C) How has Brenner's research team proved a truth.

　　D) C3 and C4 plants are important plants in determining the composition of plant communities.

　　Part V Cloze (15 minutes)

　　Directions: There are 20 blanks in the following passage. For each blank there are four choices marked A), B), C) and D) on the right side of the paper. You should choose the ONE that best fits into the passage. Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.

　　When a person walks, the movement of his head, trunk, hipbones and limbs are all reflected in changes in his body. A computer 67 these changes into a database. Later, the computers can accurately 68 him according to these changes. This is a new biological identification method and it can quickly identify an examinee 69 disturbing him. It's especially suitable for use in airports and supermarkets.

　　Everybody's voice is 70 . When a person's voice is recorded by an ___71___, its voice frequencyspectrum is called his sound print. Like a fingerprint, everybody's sound print is different. How can computers 72 his sound? First, his voice is recorded, which allows the computers to become familiar ___73___ his voice. It will then turn his sound characteristics into a ___74 of digits. These digits ___75___ the frequency, pitch and rhythm of the person's voice. These are the 76 on which the computers can distinguish his voice from 77 .

　　When that person needs to be identified, after he says only one word or two, the computers can identify him. The computers can even identify sounds coming 78 the wires. This will provide a safer 79 to electric banks and electric purchases.

　　We often bring ID cards, work cards, or driver licenses with us to ___80___ our identity. If all these cards are forgotten or lost, how can we prove 81 we are? In fact, it's not difficult to prove whom you are, because your body 82 has identifying markers. Some are physiological features, such as fingerprints, sounds, facial types and eye color. The computer can help to identify you. __83__ your features have already been stored in the database. To identify you, we have to take your picture with a camera and send it to a computer for 84 . First, the computer needs to reposition this picture according to the position of your eyes, and then starts to read the message of your physiological features such as the 85 of your pupil to the whites of your eyes and the shape of your nose. Next, it seeks matching records from the database. Finally, it makes a 86 .

67. A checks B stores C revises D modifies

　　68. A identify B distinguish C convey D strike

　　69. A without B with C for D in

　　70 A identical B similar C unique D sole

　　71. A implement B appliance C instrument D equipment

　　72. A hear B understand C record D distinguish

　　73 A to B in C on D with

　　74. A series B package C line D pair

　　75. A reverse 　　B represent C reveal D recession

　　76. A origin B cause C reason D basis

　　77 A other's B another's C each other's D one another's

　　78. A at B on C in D through

　　79. A assure B guarantee C ensure D confirm

　　80. A cause B make C prove D leave

　　81 A whom B how C what D where

　　82. A oneself B themselves C itself D himself

　　83 A Provide B Suppose C Imagine D Give

　　84. A processing B copying C coloring D revising

　　85. A size B type C ratio D shape

　　86. A recommendation B contribution C proposal D decision

　　Part VI Translation (5 minutes)

　　Directions: Complete the sentences on Answer Sheet 2 by translating into English the Chinese given in brackets.

　　87. (大学校园是否该对游客开放)is a hot topic.

　　88.We all know that he (他对学英语付出了很多努力)。

　　89. The research shows this medicine .

　　(对危害的作用大于救命作用)

　　90. We all hold strong belief that the issue can be settled .

　　(只有通过增加投资的预算)

　　91. (你不会在英语上赶上别人) without diligent work.
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