首页
登录
职称英语
A scientific discovery is often made【C1】______ before someone is able to pu
A scientific discovery is often made【C1】______ before someone is able to pu
游客
2023-11-23
11
管理
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】______ . [br] 【C11】
选项
A、from
B、in
C、toward
D、by
答案
B
解析
此题考查介词的用法。介词短语in all directions是固定说法,意为“四面八方”。例如:The crowd ran screaming in all directions.其他三个选项均无该用法。所以,只有B项符合题意。
转载请注明原文地址:https://tihaiku.com/zcyy/3211927.html
相关试题推荐
Shouldhighschoolseniorstakeagapyearbeforetheygotouniversities?Gap
Usually,therearetworeasonstopursuescientificknowledge:forthesakeof
Usually,therearetworeasonstopursuescientificknowledge:forthesakeof
Usually,therearetworeasonstopursuescientificknowledge:forthesakeof
Usually,therearetworeasonstopursuescientificknowledge:forthesakeof
ThescientificnameistheHoloceneAge,butclimatologistsliketocallour
ThescientificnameistheHoloceneAge,butclimatologistsliketocallour
OnFeb.2,2007,theUnitedNationsscientificpanelstudyingclimatechang
OnFeb.2,2007,theUnitedNationsscientificpanelstudyingclimatechang
OnFeb.2,2007,theUnitedNationsscientificpanelstudyingclimatechang
随机试题
[audioFiles]audio_eufm_j65_001(20082)[/audioFiles]A、Inapark.B、Inamuseum.C
Forthispart,youareallowed30minutestowriteanessay.Youshouldstartyo
肝硬化的组织学改变包括()。A.正常肝小叶结构破坏 B.毛细血管明显增生
学术界普遍认为,在采用大机器生产的现代工业的基础上发展起来的农业是()。A.原
通常将OCR小于的天然土程层称为超固结土。
患者,女性,47岁,糖尿病病史5年,近半年来每于夜间出现下肢不适,如初步考虑糖尿
关于补体的理化特性描述错误的是A.存在于新鲜血清及组织液中具有酶样活性的球蛋白B
变电站的110kV及以下母线电量不平衡率,一般要求不超过4%。
某工程进行现场水文地质实验,已知潜水含水层底板埋深为9.0m,设置潜水完整井,井
预防控制危险化学品事故的主要措施是替代、变更工艺、隔离、通风、个体防护和保持卫生
最新回复
(
0
)