首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
公务员
Many people believe the glare from snow causes snow blindnenss. Yet, dark glasses or not, they find themselves suffering from he
Many people believe the glare from snow causes snow blindnenss. Yet, dark glasses or not, they find themselves suffering from he
admin
2011-01-01
59
问题
Many people believe the glare from snow causes snow blindnenss. Yet, dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snowblindness, when ex- posed to several hours of "snow light".
The United States army has now determined that glare from snow does not cause snow blindness in troops in a snow-covered country. Rather, a man’ s eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of something to look at. Finding nothing, hour after hour, the eyes never stop searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid covers the eyeball in increasing quantity until vision blurs, then is observed, and the result is total, even though temporary, snow blindness.
Experiments led the army to a simple method of overcoming this problem. Scouts ahead of a main body of troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow-covered landscape. Even the scouts themselves throw lightweight, dark colored objects ahead on which they too can focus. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop scouring the snow-blanketed lanscape. By focusing their attention on one object at a time, the men can cross the snow without becoming hopelessly snowblind or lost. In this way the problem of crossing a solid white terrain is overcome.
Snow blindness may be avoided by______.
选项
A、concentrating to the solid white terrain
B、searching for something to look at in snow-covered terrain
C、providing the eyes with something to focus on
D、covering the eyeballs with fluid
答案
C
解析
由最后一段的倒数第二句可知,让眼镜专注于某一物体是避免雪盲的办法。故选C。
转载请注明原文地址:https://kaotiyun.com/show/mKBq777K
本试题收录于:
中学英语题库教师公开招聘分类
0
中学英语
教师公开招聘
相关试题推荐
教书育人是教师职业的核心理念。()
引发求知欲、感知教材、理解教材、巩固知识、运用知识和检查知识是所有课堂教学必备的六个基本阶段。()
Theevidenceforharmonymaynotbeobviousinsomefamilies.Butitseemsthatfouroutoffiveyoungpeoplenowgetonwithth
Theevidenceforharmonymaynotbeobviousinsomefamilies.Butitseemsthatfouroutoffiveyoungpeoplenowgetonwithth
Theevidenceforharmonymaynotbeobviousinsomefamilies.Butitseemsthatfouroutoffiveyoungpeoplenowgetonwithth
Therearemanykindsoffriends.Somearealways【C1】______you,butdon’tunderstandyou.Somesay"onlyafewwordstoyou,but
Therearemanykindsoffriends.Somearealways【C1】______you,butdon’tunderstandyou.Somesay"onlyafewwordstoyou,but
Oneafternoon,mysonAdamaskedme,"Areallpeoplethesameeveniftheyaredifferentincolor?"Ithoughtforaminute,
Thelocalgovernmentis______(讨论)howtohelpthepoorinthecountryside.
随机试题
汽车的制动性能主要由_______、_______、_______、_______、_______等几个方面来评价。
戏剧《俄狄浦斯王》的作者是()
完全信息价值
幼儿参观动物园后记住了猴子、老虎等一些动物形象,这属于()。
民主集中制是()。
17653,37651,57631,67531,()
行为作为民事法律关系产生、变更、消灭的法律事实()。
逻辑证明。是指运用已知的正确概念和判断,通过一定的推理,从理论上确定另一个判断的正确性的逻辑方法。以下论断中正确的有()
IhavebeenteachingforlongerthanIcaretosay,andalwaysofferacourseforenteringfreshmen.AndI’vediscoveredsomet
Ithinkitisawasteoftimetohaveremarksnot______tothesubjectunderdiscussion
最新回复
(
0
)