2009年职称英语理工类C级模拟试题(4)

　　第6部分：完形填空(第51～65题，每题1分，共15分)
　　阅读下面的短文，文中有15处空白，每处空白给出4个选项，请根据短文的内容从4个选项中选择1个最佳答案，涂在答题卡相应的位置上。
　　Avalanche and Its Safety
　　An avalanche is a sudden and rapid flow of snow, often mixed with air and water, down a mountainside. Avalanches are 51 the biggest dangers in the mountains for both life and property.
　　All avalanches are caused by an over-burden of material, typically snowpack, that is too massive and unstable for the slope 52 supports it. Determining the critical load, the amount of over-burden which is 53 to cause an avalanche, 54 a complex task involving the evaluation of a number of factors.
　　Terrain slopes flatter than 25 degrees or steeper than 60 degrees typically have a low 55 of avalanche. Snow does not 56 significantly on steep slopes; also, snow does not 57 easily on flat slopes. Human-triggered avalanches have the greatest incidence when the snow's angle of rest is 58 35 and 45 degrees; the critical angle, the angle at which the human incidence of avalanches is greatest, is 38 degrees. The rule of thumb is: A slope that is 59 enough to hold snow but steep enough to ski has the potential to generate an avalanche, regardless of the angle. Additionally, avalanche risk increases with 60 ; that is, the more a slope is disturbed by skiers, the more likely it is that an avalanche will occur.
　　Due to the complexity of the subject, winter travelling in the backcountry is never 100% safe. Good avalanche safety is a continuous 61 , including route selection and examination of the snowpack, weather 62 , and human factors. Several well-known good habits can also 63 the risk. If local authorities issue avalanche risk reports, they should be considered and all warnings should be paid 64 to. Never follow in the tracks of others without your own evaluations; snow conditions are almost certain to have changed since they were made. Observe the terrain and note obvious avalanche paths where plants are 65 or damaged. Avoid traveling below others who might trigger an avalanche.
　　51. A among B of C to D in
　　52. A when B that C who D whose
　　53. A mostly B likely C clearly D surely
　　54. A are B will be C is D was
　　55. A weight B form C risk D work
　　56. A fall B flow C roll D gather
　　57. A fall B flow C roll D gather
　　58. A among B between C with D for
　　59. A thick B thin C flat D rocky
　　60. A use B time C snow D rain
　　61. A journey B trip C fact D process
　　62. A conditions B reports C forecast D event
　　63. A increase B reduce C improve D remove
　　64. A price B effort C attention D money
　　65. A missing B grown C big D fresh
　　全国专业技术人员职称英语等级考试理工类（C级）模拟试题(二)参考答案
　　1 A 2 D 3 D 4 A 5 A 6 D 7 A 8 A 9 A 10 D 11 D 12 A 13 A 14 A 15 A
　　16 B 17 A 18 A 19 A 20 A 21 B 22 C 23 B 24 C 25 F 26 D 27 E 28 D 29 C 30 A
　　31 B 32 A 33 A 34 D 35 B 36 B 37 C 38 A 39 C 40 A 41 C 42 B 43 A 44 C 45 D
　　46 E 47 A 48 B 49 F 50 C 51 A 52 B 53 B 54 C 55 C 56 D 57 B 58 B 59 C 60 A
　　61 D 62 A 63 B 64 C 65 A