14．There are many animals in the world which are facing in the situation of disappearing．Two-thirds of the world's polar bear population could be gone by 2050if predictions（预测）of melting sea ice come true，the US Geological Survey reported on Friday．
The fate（命运） of polar bears could be even worse than that estimate（估计），because sea ice in the Arctic（北冰洋）might be disappearing faster than the available computer models predict，the geological survey said in a report aimed at determining whether the big white bear should be listed as a threatened species（濒危物种）．
"There is a definite（确定的）link between changes in the sea ice and the welfare（利益） of polar bears，"said Steve Amstrad，who led the research team．He says Arctic sea ice is already at the lowest this year and is expected to retreat（退却） farther this month．
That means that polar bears-some 16，000of them--will disappear by 2050from parts of the Arctic where sea ice is melting most rapidly，along the north coasts of Alaska and Russia，researchers said in a telephone briefing（简报）．Other polar bears could survive beyond that date but many of those could be gone by 2100，Amstrad said．By this century's end，the only polar bears left might live in the Canadian Arctic islands and along the west coast of Greenland（格陵兰岛）．"It is likely to result in loss of approximately（大约）two-thirds of the world's current polar bear population by the mid 21st century，"the report's executive summary said．
"Because the observed trajectory（轨迹）of Arctic sea ice decline appears to be underestimated by currently available models，this assessment of future polar bear status may be conservative（保守的）．"In January，the US Fish and Wildlife Service proposed listing the polar bear as a threatened species，noting polar bears depend on sea ice as a platform to hunt seals（海豹），their main food．Without enough sea ice，polar bears would be forced onto land，but they are poor hunters once they get out of the water and ice，the researchers said．The bears'disappearance would probably take place as young cubs（幼兽）failed to survive to adulthood and females were unable to reproduce successfully．
9．What was the US Geological Survey intended to do？A
A．To determine whether the polar bear was in danger．
B．To measure how fast the sea ice melts in the Arctic．
C．To check the predictions of the computer models．
D．To find out the exact number of the polar bear．
10．What causes the polar bears to disappear by 2050？B
A．The pollution of the Arctic region．
B．The sea ice melting at high speed
C．Fewer food sources being left．
D．The temperature getting colder．
11．The key to preventing polar bears dying out seems toC．
A．help young polar bears to survive the cold winter
B．have large number of seals living in the oceans
C．make sure there is enough sea ice in the Arctic
D．provide chances for adult polar bears to reproduce．
分析 本文是一篇说明文，说明了美国地质专家预测到2050年，海冰融化导致北极熊列为濒危物种，但是北极熊比预计的更糟，因为在北极海水的消失比电脑预测的更快，地质勘察报告旨在确定是否将北极熊列为濒危物种．
解答 9：A细节题，由第二段最后一句"the geological survey said in a report aimed at determining whether the big white bear should be listed as a threatened species"地质调查报告中称，旨在确定大白熊应该列为濒危物种可以知道答案，故选A．
10：B细节题．由第一段"Two-thirds of the world's polar bear population could be gone by 2050 if predictions of melting sea ice hold true，the US Geological Survey reported on Friday．"世界上三分之二的北极熊数量可能在2050年灭绝如果海冰融化适用的预测，美国地质调查局在周五报道．可以知道答案，所以选B．
11：C推理题，由倒数第二段最后一句"noting polar bears depend on sea ice as a platform to hunt seals，their main food．"北极熊主要依靠海冰来捕食海豹，这是它们的主要食物．可以推出答案，所以选C．
点评 本文是一个新闻报道类阅读，题目涉及多道细节理解题，做题时结合原文和题目有针对性的找出相关语句进行仔细分析，结合选项选出正确答案．推理判断题也是要在抓住关键句子的基础上合理的分析才能得出正确答案，切忌胡乱猜测，一定要做到有理有据．
