(精校版)20xx年北京英語(yǔ)高考試題文檔版(含答案)-展示頁(yè)
2025-07-03 02:31本頁(yè)面
【正文】 l, ＂she explains, ＂The wax worm evolved a method or system to break this bond. ＂Jennifer DeBruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But pared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify the cause of the breakdown. Is it an enzyme produced by the worm itself or by its gut microbes(腸道微生物)?Bertocchini agrees and hopes her team’s findings might one day help employ the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process — not simply ＂millions of worms thrown on top of the plastic.＂43. What can we learn about the worms in the study?A. They take plastics as their everyday food.B. They are newly evolved creatures.C. They can consume plastics.D. They wind up in landfills.44. According to Jennifer DeBruyn, the next step of the study is to .A. identify other means of the breakdownB. find out the source of the enzymeC. confirm the research findingsD. increase the breakdown speed45. It can be inferred from the last paragraph that the chemical might .A. help to raise wormsB. help make plastic bagsC. be used to clean the oceansD. be produced in factories in future46. What is the main purpose of the passage?A. To explain a study method on worms.B. To introduce the diet of a special worm.C. To present a way to break down plastics.D. To propose new means to keep ecobalance.DPreparing Cities for Robot CarsThe possibility of selfdriving robot cars has often seemed like a futurist’s dream, years away from materializing in the real world. Well, the future is apparently now. The California Department of Motor Vehicles began giving permits in April for panies to test truly selfdriving cars on public roads. The state also cleared the way for panies to sell or rent out selfdriving cars, and for panies to operate driverless taxi services. California, it should be noted, isn’t leading the way here. Companies have been testing their vehicles in cities across the country. It’s hard to predict when driverless cars will be everywhere on our roads. But however long it takes, the technology has the potential to change our transportation systems and our cities, for better or for worse, depending on how the transformation is regulated.While much of the debate so far has been focused on the safety of driverless cars(and rightfully so), policymakers also should be talking about how selfdriving vehicles can help reduce traffic jams, cut emissions(排放) and offer more convenient, affordable mobility options. The arrival of driverless vehicles is a chance to make sure that those vehicles are environmentally friendly and more shared.Do we want to copy — or even worsen — the traffic of today with driverless cars? Imagine a future where most adults own individual selfdriving vehicles. They tolerate long, slow journeys to and from work on packed highways because they can work, entertain themselves or sleep on the ride, which encourages urban spread. They take their driverless car to an appointment and set the empty vehicle to circle the building to avoid paying for parking. Instead of walking a few blocks to pick up a child or the dry cleaning, they send the selfdriving minibus. The convenience even leads fewer people to take public transport — an unwele side effect researchers have already found in ridehailing(叫車) services.A study from the University of California at Davis suggested that replacing petrolpowered private cars worldwide with electric, selfdriving and shared systems could reduce carbon emissions from transportation 80% and cut the cost of transportation infrastructure(基礎(chǔ)設(shè)施) and operations 40% by 2050. Fewer emissions and cheaper travel sound pretty appealing. The first mercially available driverless cars will almost certainly be fielded by ridehailing services, considering the cost of selfdriving technology as well as liability and maintenance issues(責(zé)任與維護(hù)問(wèn)題). But driverless car ownership could increase as the prices drop and more people bee fortable with the Policymakers should start thinking now about how to make sure the appearance of driverless vehicles doesn’t extend the worst aspects of the carcontrolled transportation system we have today. The ing technological advancement presents a chance for cities and states to develop transportation systems designed to move more peopl
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