首页
登录
职称英语
What happened to the London underground railway about three decades ago? [br] [
What happened to the London underground railway about three decades ago? [br] [
游客
2023-11-22
60
管理
问题
What happened to the London underground railway about three decades ago? [br]
The world’s first completely automatic railway has been built under the busy streets of London. The railway is called the Victoria Line, and it is part of the complete London underground railway.
The new Victoria Line was opened in 1969. This new line was very different from the others.
The stations on the other lines need a lot of workers to sell tickets, and to check and to collect them when people leave the trains. This is all different of the Victoria Line. Here a machine checks and collects the tickets, and there are no workers on the platforms.
On the train, there is only one worker. If necessary, this man can drive the train. But usually he just starts it; it runs and stops by itself. The trains are controlled by electrical signals which are sent by the so-called "command spots". The command spots are the same distance apart. Each sends a certain signal. The train always moves at the speed that the command spots allow. If the command spot sends no signals, the train will stop.
Most of the control work is done by computers. The computers also fix the train’s speeds, and send the signals to the command spots.
Other machines make sure that the trains are always a safe distance apart. If one train stays too long at a station, the other trains will then automatically move slower. So there is no danger of accidents on the line.
选项
A、It will stop automatically.
B、It will move on at the same speed.
C、It will gradually slow down.
D、It will keep a safe distance from the other trains.
答案
A
解析
转载请注明原文地址:https://www.tihaiku.com/zcyy/3210516.html
相关试题推荐
Eveniftheyproducednootherpositiveresult,theattacksontheLondonUnde
PassageThree(1)Givenallthathashappenedonsomanycampusesover
PassageThree(1)Givenallthathashappenedonsomanycampusesover
PassageThree(1)Givenallthathashappenedonsomanycampusesover
PassageThree(1)LondonmaybeEurope’scommercialcapital,butnotall
PassageTwo(1)Overthepastfewdecades,youngwomenhavebeenclimbi
PassageTwo(1)Overthepastfewdecades,youngwomenhavebeenclimbi
PassageTwo(1)Overthepastfewdecades,youngwomenhavebeenclimbi
Overthepasttwodecades,countriesintheworldhavebecomemoreandmore
Overthepasttwodecades,countriesintheworldhavebecomemoreandmore
随机试题
Thetouristtradeisbooming.Withallthiscomingandgoing,you’dexpect
IfyoulookcloselyatsomeoftheearlycopiesoftheDeclarationofIndepen
编制资金使用计划,确定、分解费用监理目标,对费用控制进行风险分析并制定防范性对策
2017年1月1日,甲公司采用分期付款方式购入一套大型设备,当日投入使用。合同约
患者症见腹大胀满,按之如囊裹水,甚则下肢水肿,脘腹痞胀,大便溏,小便少,精神困倦
属于酯树脂类的药材是A:乳香B:血竭C:阿魏D:没药E:松香
Lb3A2182要使负载上得到最大的功率,必须使负载电阻与电源内阻()。(
根据下列资料回答问题。 《河北省2010年国民经济和社会发展统计公报》显示:河
2012年1-4季度人均消费支出八大类中,家庭设备用品及服务比医疗保健多:(
因欺诈、胁迫而订立的施工合同可能是无效合同,也可能是可撤销合同。认定其为无效合同
最新回复
(
0
)