考博易错题(2019/1/11) |
第1题: Even when textbooks are ______ through a school system, methods of teaching may vary greatly. A.commonplace B.standardized C.competitive D.generalized |
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第2题:The climate ofEarth is changing.Climatologists are confident that over the past century, the global average surface temperature has increased by about half a degreeCelsius. This warming is thought to be at least partly the result of human activities, such as the burning of fossil fuels and the clearing of forests for agriculture.As the global population grows and national economies expand, the global average temperature is expected to continue increasing by an additional 1.0℃ to 3.5℃ by the year 2100. Climate change is one of the most important environmental issues facing human- kinD、Understanding the potential impacts of climate change for natural ecosystems is essential if we are going to manage our environment to minimize the negative consequences of climate change and maximize the opportunities that it may offer.Because natural ecosystems are complex, nonlinear systems, it follows that their responses to climate change are likely to be complex.Climate change may affect natural ecosystems m a variety of ways. In the short term. climate change can alter the mix of plant species in land ecosystems such as grasslands. In the long term, climate change has the potential to dramatically alter the geo- graphic distribution of major vegetation types savannas, forests, and climate change can also potentially alter global ecosystem processes, including the cycling of carbon, nitrogen, phosphorus, and sulfur. Moreover. changes in these ecosystem processes can affect and be affected by changes in the plant species of the ecosystem and vegetation type.All of the climate change-induced alterations of natural ecosystems affect the services, that these ecosystems provide to humans. The global average surface temperature increase of half a degreeCelsius observed over the past century has been in part due to differential changes in daily maximum and minimum temperatures, resulting in a narrowing of the diurnal temperature range.Decreases in the diurnal temperature range were first identified in the United States, where large-area trends showed that maximum temperatures have remained constant or increased only slightly, whereas minimum temperatures have increased at a faster rate. In this issue,Al-ward et al. report on the different sensitivities of rangeland plants to minimum temperature increases. Which of the following is NOT mentioned as a reason for the global warming A、The burning of fuels such as coal or oil. B、The clearing of forests. C、The cultivation of farmland, D、The negative consequences of human activities. |
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第3题: Prosperous alumni helped make 2006 a recorded fund-raising year for colleges and universities, which hauled in $ 28 billion—a 9.4 percent jump from 2005. |
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第4题:New data has______that the damage to the ozone layer is not confined to the southern hemisphere.
A.ratified B.confirmed C.assured D.approved |
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第5题:On its last flight to the moon in 1972, theApollo spacecraft ______ with a record lunar stay of seventy-five hours, which aroused worldwide excitement. A、wound up B.cut up C.turned up D.pulled up |
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