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
A scientific discovery is often made【C1】______ before someone is able to put it to use.【C2】______ , scientists discovered how to
A scientific discovery is often made【C1】______ before someone is able to put it to use.【C2】______ , scientists discovered how to
admin
2009-02-10
63
问题
A scientific discovery is often made【C1】______ before someone is able to put it to use.【C2】______ , scientists discovered how to split atoms decades【C3】______ the invention of the atomic bomb and the use of【C4】______ power to produce electricity. But sometimes discovery and【C5】______ happen at the same time, as occurred more than thirty years ago【C6】______ the discovery of coherent light and the invention of the laser.
The word laser【C7】______ "light amplification by stimulated emission of radiation. To many people, lasers are very mysterious, but a laser is simply a【C8】______ that produces a strong light. The light from the laser is called【C9】______ light because it is light that only moves in one direction.【C10】______ , incoherent light, like the light from the sun or light from a bulb, moves away from its source【C11】______ all directions, so its strength is very spread out. The light from a laser, moving in only one direction and【C12】______ in a narrow beam, is much stronger. Laser light is created by a【C13】______ called stimulated emission. In this process, the atoms of a certain substance, such as a crystal or a gas, are excited 【C14】______ that they produce coherent light. A person working with a laser can aim this coherent light,【C15】______ a laser beam, in any direction.
As soon as the laser was developed, scientists began thinking of practical applications【C16】______ it. One of the earliest uses was to make extremely precise measurements of distance and speed.【C17】______ , the distance to the moon was measured to within a foot, and the speed of light was measured to 【C18】______ a thousandth of a mile per second. As time【C19】______ , many more applications for the laser were【C20】______ .
【C13】
选项
A、process
B、way
C、period
D、device
答案
A
解析
此题考查名词的用法。看到该句中的同位语stimulated emission,就可以得出结论:激光是一个“过程”(process),而不是“方法”(way)、“时间段”(period)或者“装置,/机制”(device)。故A项符合题意。
转载请注明原文地址:https://kaotiyun.com/show/IE6K777K
0
专业英语四级
相关试题推荐
FormanyyearsitwascommonintheUnitedStatestoassociateChineseAmericanswithrestaurantsandlaundries.Peopledidnot
A、Aregularstudyprogramisessentialtolearninganotherlanguage.B、Eatingeggsandtoastisimportantforlearninganotherl
Belowaretwoexcerptsonanimportantconcernofmusicindustry:whetheritiscorrecttosharemusicwithoutpaying.Readt
A、Peopledonotfeelabigdeal.B、Peoplefeelcompletelyoccupied.C、Peoplefeelshockedandhurt.D、Peoplefeelangryandexas
Beijingiscontemplatingchargingcongestionfeesforcarsthatenterthecitycenterduringpeakhoursinabidtoeasethetra
ThemostimportantthingnowisforDemocratsnottopanic.Despitewhatyourgutistellingyou,thisisnottheendofthewor
ScientistssaidThursdaythatanewAIDSvaccine,thefirsteverdeclaredtoprotectasignificantminorityofhumansagainstth
Socialnetworkingisgaininggreatpopularitythesedays.Manypeoplebelieveithasmadeourlifemoreconvenient,butotherst
ThefollowingtwoexcerptsareaboutthepracticeofrentingboyfriendsandgirlfriendsfortheChineseNewYear.Fromtheexcer
WhatwasSulaimanHashim?
随机试题
如下图,路口导向线用于辅助车辆转弯行驶。
焊接电流太小,易引起()缺陷。
一患者突然咯血200mL,既往间断咳嗽,咳脓痰20余年。该患者咯血最可能的原因是()
患者干咳,咳声短促,痰中带有血丝,色鲜红,胸部隐隐闷痛,午后自觉手足心热,皮肤干灼,口干咽燥,疲倦乏力,纳食不香,舌边尖红,苔薄白,脉细数。治疗应首选的方剂是
用某些物理化学方法将药物传输到特定部位发挥药效的制剂为被动靶向制剂。()
下列属于安全检查的扣分标准有()。
导游服务质量考核的ASK原则指的是()。
小学教师夏某安排成绩比较落后的两名同学考试时间上自习。教师夏某的做法()。
“统计与概率”的教学设计,一定要注重内容的时代性,所选()要贴近学生的生活实际,是学生有能力感受的现实,不能离学生太远。
Mysuggestion______weshouldsticktoouroriginalplanwasfinallyaccepted.
最新回复
(
0
)