The polar bear is found in the Arctic Circle and some big land masses as far south as Newfoundland. While they are rare north of 88°,there is evidence ___61___ they range all the way across the Arctic, and as far south as James Bay in Canada. It is difficult to figure out a global population of polar bears as much of the range has been ___62___ (poor) studied; however, biologists calculate that there are about 20,000-25,000 polar bears worldwide.
Modem methods ___63___ tracking polar bear populations have been employed only since the mid-1980s, and are expensive ___64___ (perform) consistently over a large area. In recent years some Inuit people in Nunayut ___65___ (report) increases in bear sightings around human settlements, leading to a ___66___ (believe) that populations are increasing. Scientists have responded by ___67___ (note) that hungry bears may be congregating(聚集) around human settlements, leading to the illusion(错觉) that populations are ___68___ (high) than they actually are. Of ___69___ nineteen recognized polar bear subpopulations, three are declining, six ___70___ (be) stable, one is increasing, and nine lack enough data.
【答案】61. that 62. poorly 63. of/for 64. to perform 65. have reported
66. belief 67. noting 68. higher 69. the 70. are
【解析】
【文章大意】 本文为科普类说明文。文章向我们介绍了目前北极熊的生存现状。近年来，在人类居住的地方看到北极熊的次数有所增加，这导致人们错误地认为北极熊的数量在上升，可事实并非如此。
61. that 考查名词性从句。根据句子结构分析可知，主句为there be句型，且结构完整，空格后为同位语从句，解释说明中心词evidence内容，故填that。
62. poorly 考查形容词副词。分析可知，此处用副词poorly修饰谓语动词has been studied，意为“研究很少”。故填poorly。
63. of/about 考查介词。此处tracking polar bear populations作Modern methods的定语，methods of/for doing sth. 意为“……的方法”。故填of/for。
64. to perform考查非谓语动词。主系表结构之后，常用不定式作原因或目的状语（主语+be +adj. + to do） 。句意：跟踪北极熊的现代方法只是在二十世纪八十年代以来开始采用，且在如此大区域内持续采用是很昂贵的。故填to perform。
65. have reported 考查动词时态。根据上下文语境，尤其是时间状语in recent years可知，句中需用现在完成时态。故填have reported。
66. belief考查词性转换。由其前不定冠词和其后that引导的同位语从句可知，空格处需填名词形式。故填belief。
67. noting 考查非谓语动词。介词by后填动名词形式，此处表示主动故填noting。句意：对此，科学家们的回应是饥饿的熊可能正聚集在人类聚居地的周围。note在此处为动词，意为“指出”。
68. higher 考查形容词比较级。根据其后than they actually are可知，此处需用形容词的比较级，故填higher。
69. the 考查定冠词。此处特指“在已知的19个北极熊亚种群中”。故填定冠词the。
70. are 考查主谓一致。根据three are declining，此处数词six作主语，代指前文中的“polar bear subpopulations”，故需用复数谓语，时态为一般现在时。故填are。
