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
外语
What do cats’ eyes and highway reflector signs have in common? They both act as retro-reflectors(反响反射器). Almost everyone has
What do cats’ eyes and highway reflector signs have in common? They both act as retro-reflectors(反响反射器). Almost everyone has
admin
2013-12-08
35
问题
What do cats’ eyes and highway reflector signs have in common? They both act as retro-reflectors(反响反射器).
Almost everyone has noticed the frightening appearance of animals at night, as their eyes seem to glow in reflected light. One may think that just as reflective highway signs alert the motorists to many road hazards, so early man was often warned of danger by light from his campfire reflected in the eyes of lurking(潜伏)predators. In both cases, the light is ret-roreflected, giving it a particularly bright appearance.
The principles of retroreflection have been understood for centuries. However, it is only within the last fifty or sixty years, with the wide use of the automobile, that this area of optics(光学)has received important commercial application. Today, the uses of retroreflective materials are many. They are applied to bicycles and motor vehicles to make them more visible at night. And they assist pilots by improving the visibility of runway markers.
Large sums are spent for retroreflective materials, but purchasers have often found it difficult to specify performance for the materials they buy. Performance is of concern not only from the standpoint of the brightness of reflected light, but also from the standpoint of its color. It is important, for example, that the yellow hues(色调)in warning signals be of consistent color quality on all road signs so the driver can rely on color, as well as shape, to discern the signs’ meanings. Seven colors — silver, blue, yellow, red, green, brown and orange — are currently used for marking the interstate highway system.
The word "predator"(Para. 2)most probably means "______".
选项
A、early man
B、wild animal
C、evil person
D、campfire
答案
B
解析
本题属于词汇语义题。我们知道,文章在前两段谈论的是动物的眼睛和公路反光标志牌的共同之处。据此判断,第二段第二句讨论的应是这两者的警戒作用;而既然该句前半部分说的是公路反光标志牌,那么后半部分涉及的则应是动物的眼睛。因此,在四个选项中,B)的意思最为贴切。故选B)。
转载请注明原文地址:https://kaotiyun.com/show/oyDO777K
0
成人本科学位英语
相关试题推荐
Lifereallyshouldbeonelongjourneyofjoyforchildrenbornwithaworldofwealthattheirfeet.Internationallyfamous
Humanbeingsactinadifferentwayfromthatofanimalsjustbecausetheycanspeakwhileanimalscannot.Eventhecleverestan
Theagriculturalrevolutioninthenineteenthcenturyinvolvedtwothings:theinventionoflabor-savingmachineryandthedevel
Themarketisaconcept.Ifyouaregrowingtomatoesinyourbackyardforsaleyouareproducingforthemarket.Youmightsell
Anallowance(零花钱)isanimportanttoolforteachingkidshowtobudget,saveandmaketheirowndecisions.Childrenrememberan
Somepeoplebelievethatinternationalsportcreatesgoodwillbetweenthenationsandthatifcountriesplaygamestogetherthey
Alanguageisasignalingsystemwhichoperateswithsymbolicvocalsounds,andwhichisusedbyagroupofpeopleforthepurpo
Woman:IsJanereadytogototheairport?Man:Ready?Shehasn’tevenfinishedpacking.Question:Whatdoesthemanmean?
Man:Wouldyouliketojoinusforaridearoundtheharbor?Woman:Whatapleasantwaytospendahotday!Question:Whatdoes
Muchunfriendlyfeelingtowardscomputershasbeenbasedonthefearofwidespreadunemploymentresultingfromtheirintroductio
随机试题
根据以下资料,回答以下问题。在2008年8月8日至24日奥运会期间,北京市的空气质量不仅天天达标,而且有10天达到一级,全面兑现了对奥运会空气质量的承诺。下图是2008年1~8月北京市大气质量检测情况,图中一、二、三、四级是空气质量等级,一级空气
已知某测点压力约为10MPa,要求其测量误差不超过±0.1MPa。试在平稳压力和波动压力下分别确定该测点用的压力表标尺范围。
患者,女性,18岁,釉质半透明度有轻度改变,可见少量白色斑纹,按照Dean氟牙症分类标准,诊断氟牙症为
在特定条件下接触某种水平的化学毒物不引起机体出现任何损害效应的概率,称
患者,女,60岁,胃癌晚期,体温40℃,护士遵医嘱给患者行乙醇拭浴降温。行乙醇拭浴后,给患者重测体温的时间为
某500kV变电所中,设有一组单星形接线串联了电抗率为12%电抗器的35kV电容器组,电容器组每组单联段数为4,此电容器组中的电容器额定电压应选为:
依据《安全生产法》的规定,下列关于安全监管人员履行监管职责的说法,错误的是()。
人工挖土方,土壤系潮湿的黏性土,按土壤分类为二类土(普通土)。测验资料表明,挖1m3需消耗基本工作时间60min,辅助工作时间、准备与结束工作时间、不可避免中断时间、休息时间的比率分别为2%、2%、1%、20%,则产量定额约为()m3/
下列关于票据付款人的责任,说法正确的为()。
下列关于转基因植物的叙述,正确的是()。
最新回复
(
0
)