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
Complete the table below. Write NO MORE THAN TWO WORDS AND/OR A NUMBER for each answer. Talking about the history of bikes
Complete the table below. Write NO MORE THAN TWO WORDS AND/OR A NUMBER for each answer. Talking about the history of bikes
admin
2017-02-25
78
问题
Complete the table below.
Write NO MORE THAN TWO WORDS AND/OR A NUMBER for each answer.
Talking about the history of bikes
Good afternoon, ladies and gentlemen. I’d like to take this opportunity to welcome you to our exhibition, "Two Centuries of the Bike". Let’s stroll around the exhibition, shall we?
Although there were a few early efforts back in the 1700s, you didn’t really see many bikes till, say, the 1830s in England. Bikes were a response to the rapid growth of cities early in the 19th Century. Cities like London were getting too big to walk across! The early bike let people travel with less effort than walking. Plus a bike was a lot cheaper than a horse!
Think of it. No one invented a bike for, what, five thousand years of human history? Why did people do it then? Probably because this was the start of the Machine Age: people wanted machines to do all the work.
There were some drawbacks however. For one thing, there were no pedals. You simply pushed yourself along using your feet. Kind of like today’s skateboard. That meant you went fairly slow. And uphill, you actually worked harder, pushing that two-wheeler. Plus, the wheels were made of wood covered with metal, as you can see from this model. So the downside was that the ride was quite uncomfortable on most roads. Only a few gadget lovers had or used them.
By the 1860s, though, improvements were being made. As you can see from this specimen, metal frames had become the rule. They’re more durable than wood, and they don’t warp in the rain. The biggest improvement however was the development of the chain and sprocket system. They are connected. This meant you did not push the bike. You used pedals just like today. You had to try harder to balance, so it took some practice to figure out how to use the pedals. But it made the ride so much easier. As a result, the good thing was that you could ride a lot more smoothly and with very little effort.
By the 1880s, another big change was the use of rubber wheels. These became pretty common at that time. Though the first ones were solid rubber, the ride was a good deal more comfortable than the old iron and wood system. This is a big consideration because the faster you go, the more you feel every bump. Air-filled tyres - "pneumatic tyres" - didn’t really come into use till around the year 1900, as you can see from this exhibition over here. That made the ride even more comfortable.
So, by 1890 or so, people were going a lot faster and a lot more smoothly. There was one problem when you were going quickly and comfortably: "OH NO! HOW DO I STOP"?! Yes, we all laugh now. But for a long time, the only way to stop was drag your feet. That didn’t work very well and it would be dangerous if you were going fast. In the crowded cities of those years -New York, Chicago, and so on - you would get killed if you couldn’t stop for, say, a streetcar.
Plus look at this bike. The front wheel is nearly a meter and two-thirds tall! They made them that way so you could see over people and wagons. But, you couldn’t drag your feet. This model is called a "velocipede" - a "speed pedal." Another characteristic of the bike in this period is that it has two equal-sized wheels, which signaled a big change in bikes.
For with the velocipede, brakes appeared. If you wanted to stop, you just pushed the pedal backwards. Doing that stopped the back wheel of the bike. This technique worked a lot better than dragging your feet, or jumping off the high seat there! This meant that bikes became a great deal safer. It would have been safer if people wore helmets, but the first bicycle helmet wasn’t invented until years later, and even then it was little more than a leather ballcap. It really wasn’t until the 1970s that the bike helmet was modified to provide some real protection.
Before continuing on to look at developments since the 1890s, let’s say a word more about safety. Everyone knows if you’re going downhill, you can get going dangerously fast. To go more than a hundred kilometres an hour isn’t all that difficult! But even on level ground it’s easy to go too quickly. On a city street, today’s bicycles can be ridden at a speed of over forty miles an hour, over a short distance. That’s about sixty-four kilometres an hour. Remember you’re on a bike, not in a car. There’s nothing to protect you. People are killed in single-bicycle accidents every day, just from hitting the road.
A good rule to remember is, if you’re going faster than the cars, slow down. And please wear a helmet. Nearly one-quarter of the epilepsy cases come from head injuries in accidents on bikes and motorcycles. I didn’t mean to scare you, but safety is everyone’s business.
What? Now that’s a good question. Why are today’s bikes so much faster? Well it’s not just that today’s athletes are faster. The answer is partly mechanical. If you look closely here, at the back wheel you’ll see a number of gears. Changing gears is what makes those fast speeds possible. You can shift gears depending on the terrain and how hard you wish to pedal. So you can put it on a higher gear for downhill, and a lower gear for uphill travel to make it easier to climb that slope. You’ll notice this gear-shifting mechanism is attached at the back wheel, and when the rider shifts on the handlebar gear-shifter, the chain moves to the appropriate sprocket. And, speaking of changing gears, let’s look over here at our "Tour de France" exhibit……
选项
答案
safer
解析
safer本题也是要填写advantage,如先前所分析,多数应填写形容词,只不过此题与前一题相隔较远,很容易使人怀疑自己是不是听过了。其实对于这种相隔较远的题目,录音一般会间隔40-60秒。同学们可以据此更好地把握答案所在。
转载请注明原文地址:https://kaotiyun.com/show/fn8O777K
本试题收录于:
雅思听力题库雅思(IELTS)分类
0
雅思听力
雅思(IELTS)
相关试题推荐
Somepeoplethinkthestudentsshouldtakethesubjectswhicharedecidedbythegovernmentintheuniversity.Othersthinkthat
Associetychanges,moreandmorepeopledonotwanttostayinonecareerorjob.Manypeoplechangetheircareersandjobs.
Agreatnumberofpeoplethinkthatthosewithuniversityeducationshouldgethigherpaythanthosewithout,fortheybelievet
Whatdoyouimaginearetheadvantagesanddisadvantagesofworkingabroad,asfarasindividualsandcountriesareconcerned?
Schoolingisnolongernecessary,sincemoreandmoreinformationisaccessibleontheInternet,andstudentscanstudyjustas
Questions28-29Completethenotes,whichshowhowtheapproachestodefining’talent’havechanged.ChooseONEorTWOWORDSfro
Questions28-29Completethenotes,whichshowhowtheapproachestodefining’talent’havechanged.ChooseONEorTWOWORDSfro
SpotthedifferenceATaxonomichistoryhasbeenmadethisweek,atleastaccordingtotheWorldWildlifeFund(WWF),aconserv
Classifythe.followinggroupsofpeopleaccordingtowhethertheybelieveA.Supplementationmayhaveapositiveeffect.B
Lookatthelistbelowoftheusesofglass.Accordingtothepassage,statewhethertheseusesexisttoday,willexistinthe
随机试题
A.支气管哮喘B.支气管扩张C.慢性支气管炎,肺气肿D.支气管肺癌E.特发性肺间质纤维化两肺散在湿啰音,伴哮鸣音及呼气相延长
患者,男,54岁。咳嗽气粗,痰多痰黄,面赤身热,口干欲饮,舌红苔黄腻,脉滑数。其证候是
混凝土棱柱体抗压弹性模量试验中,试件尺寸与棱柱体轴心抗压强度试验试件尺寸相同,每组为同龄期同条件制作和养护的试件6个,其中3个试件用于测定轴心抗压强度,提供弹性模量试验的加荷标准,另3个则用作弹性模量试验。请回答下列问题:在仪器设备调整到位后,即可进行
在置业投资中,最高运营费用比率越高,则预示着投资项目的净经营收入越高,项目抵抗风险的能力越弱。()
某公司在南方某地承接一低压蒸汽架空外管线工程。根据合同,蒸汽管道系统必须在l个月内完成,当时正值梅雨季节,据当地气象部门预报,将有20天左右的连续阴雨,为保证工程进度和工程质量,尤其是要保证焊接质量和进度,施工单位决定采取地面组组装、分段吊装的施工方法,从
根据《安全生产许可证条例》,企业取得安全生产许可证应当具备的条件有()。
据存货经济订货模型,经济订货量是能使订货总成本与储存总成本相等的订货批量。()
集体是群体发展的()。
Firecanhelppeopleinmanyways.Butitcanbeverydangerous.Firecanheatwater,warmhouses,givelightandcook.Butfire
______(不管观众中的一些人如何难为他).thecomedianalwayshadaquick,sharpreply.
最新回复
(
0
)