第一节 完形填空
Most polar(北极）bears could disappear by the end of the century because of global warming, scientists say.
According to a study in Nature Climate Change, the number of most polar bears will rapidly by 2080. There are two reasons. One is that the sea ice is melting. Polar bears catch seals to eat on the ice. ice, they have to stay on land. But there is no food on land to support so many bears. The animals could die from hunger. The other reason is that mother bears may not be fat enough to milk for their babies, so some bears could stop having babies.
Polar bears are land animals that eat meat on the planet. They help control other kinds of animals. Losing them would break the balance of ecological system in their living place.
The Arctic(北冰洋）is the to polar bears. The Arctic Sea ice usually melts in spring and summer, then grows in winter. But now, the is taking longer to grow back. Scientists say the Arctic is warming twice as fast as the rest of the planet. The study also shows it is possible to slow Arctic melting. Greenhouse gas could lead to climate change. In order to avoid creating greenhouse gas, the world should try to stop burning coal and driving cars.
Saving the bears is us. Holland, one of the writers of the study, says,
"I believe there is hope, but humans need to act to make that hope come true." Let's take action to protect our earth and save polar bears.
()1. A. develop B. fall C. increase D. improve
()2. A. Through B. Across C. Without D. Except
()3. A. enough B. good C. sweet D. delicious
()4. A. protect B. process C. prepare D. produce
()5. A. the largest B. the loveliest C. the simplest D. the luckiest
()6. A. room B. family C. house D. home
()7. A. sea B. ice C. plant D. animal
()8. A. if B. when C. that D. whether
()9. A. up to B. hard on C. good with D. thankful to
()10. A. widely B. clearly C. quickly D. quietly

1-5 BCADA 6-10 DBCAC

1. 根据文章首句提到多数北极熊会因全球变暖在本世纪末消失，可知此处指到2080年北极熊的数量会快速下降，fall意为“下降”，其余选项develop（发展）、increase（增长）、improve（提升）均不符合语境。
2. 前文提到北极熊原本在冰上捕捉海豹，海冰融化后没有冰的话，它们就只能待在陆地上，Without意为“没有”，符合逻辑。
3. 后文提到北极熊可能会饿死，说明陆地上没有足够的食物来养活这么多北极熊，enough意为“足够的”，符合语境。
4. 此处指熊妈妈需要足够胖才能为幼崽产奶，produce milk是固定表达，意为“产奶”，produce符合句意。
5. 根据常识，北极熊是地球上体型最大的陆地食肉动物，the largest符合事实和后文提到的它们能调控其他动物数量的语境。
6. 此处表达北冰洋是北极熊的家园，home带有“栖息地、家园”的归属感含义，比普通的house（实体房屋）、room（房间）、family（家庭）更贴合语境。
7. 前文提到北冰洋的海冰通常春夏融化、冬天重新形成，此处指现在冰重新形成需要花费更长时间，ice对应前文的sea ice，符合逻辑。
8. 此处动词show后接陈述事实的宾语从句，表达“减缓北极融化是有可能的”这一确定结论，用that引导宾语从句，符合语法规则。
9. 固定搭配be up to sb意为“取决于某人、是某人的责任”，此处指拯救北极熊是我们的责任，符合文意。
10. 前文提到现在仍有希望，但是人类需要快速行动才能让希望成真，quickly（快速地）符合呼吁人们立刻采取行动的语境。