Model Test Five Part I Writing (30 minutes)Directions: For this part, you are allowed 30 minutes to write a short essay entitled My View on off-campus Room Renting. You should write at least 120 words figlowing the outline given below: I.很多大学生在校外租房住; 2.学生校外租房的主要原因; 3.校外租房的利弊.My View on Off-campus Room Renting Part II Reading Comprehension (Skimming and Scanning) (15 minutes)Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1.For questions 1 - 7, choose the best answer from the four choices marked A), B), C) and D).For questions 8 - 10, complete the sentences with the information given in the passage.ChangeAs relentlessly bad as the news about global warming seems to be, with ice at the poles melting faster than scientists had predicted and world temperatures rising higher than expected, there was at least a reservoir of hope stored here in Canadas vast forests.The countrys 1.2 million square miles of trees have been called the lungs of the planet by ecologists because they account for more than 7 percent of Earths total forest lands. They could always be depended upon to suck in vast quantities of carbon dioxide, naturally cleansing the world of much of the harmful heat-trapping gas.But not anymore. In an alarming yet little-noticed series of recent studies, scientists have concluded that Canadas precious forests, stressed front damage caused by global warming, insect sand persistent fires, have crossed an ominous (危险的) line and are now pumping out more climate-changing carbon dioxide than they are sinking. Worse yet, the experts predict that Canadas forests will remain net carbon sources, as opposed to carbon storage sinks, until at least 2022, and possibly much longer.We are seeing a significant distortion of the natural trend, said Werner Kurtz, senior research scientist at the Canadian Forest Service and the leading expert on carbon cycles in the nations forests. Since 1999, and especially in the past five years, the forests have shifted from being a carbon sink to a carbon source.Translation: Earths lungs have come down with emphysema (肺气肿). Canadas forests are no longer our friends.So serious is the problem that Canadas federal government effectively wrote off the nationsforests in 2007 as officials submitted their plans to abide by the international Kyoto Protocol, which obligates participating governments to reduce their greenhouse gas emissions.Under the Kyoto agreement, governments are permitted to count forest lands as credits, whencalculating their national carbon emissions. But Canadian officials, aware of the scientific studies showing that their forests actually are emitting excess carbon, quietly omitted the forest lands from their Kyoto compliance calculations.The forecast analysis prepared for the government . indicates there is a probability that forests would constitute a net source of greenhouse gas emissions, a Canadian Environment Ministry spokesman told the Montreal Gazette.Canadian officials say global warming is causing the crisis in their forests. Inexorably risingtemperatures are slowly drying out forest lands, leaving trees more susceptible to frees, which release huge amounts of carbon into the atmosphere.Higher temperatures also are accelerating the spread of a deadly pest known as the mountain pine beetle, which has destroyed pine forests across British Columbia and is threatening vital wood in the neighboring province of Alberta. More than 50,000 square miles of British Columbias pine forest have been stricken so far with the markers of death: needles turn bright red before failing off the tree.Bitter cold Canadian winters used to kill off much of the pine beetle population each year, naturally keeping it in check. But the milder winters of recent years have allowed the insect to grow rapidly. Thats whats causing some of our forests to switch from a carbon sink position to a source position, said Jim Snetsinger, British Columbias chief forester. Once those infested trees are killed by the pine beetle, they are no longer taking in carbon-they are giving it off.Snetsinger noted that eventually, over the course of a generation, some of the dying forests will begin to regenerate and once again begin storing more carbon than they release. But for the foreseeable future, experts say, their models show that Canadas forests will stay stuck in a bad global warming cycle, both succumbing to the effects of climate change and, as they decay and release more carbon, helping to accelera