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、They made them by knives. B、They found adequate stones. C、They used bones of animals. D、They made tools by hitting stone again
A、They made them by knives. B、They found adequate stones. C、They used bones of animals. D、They made tools by hitting stone again
admin
2009-04-23
27
问题
Human beings have used tools for a very long time. In some parts of the world you can still find tools that people used more than two million years ago. They made these tools by hitting one stone against another. In this way they broke off pieces from one of the stones. These chips of stone were usually sharp on one side. People used them for cutting meat and skin from dead animals, and also for making other tools out of wood. Human beings needed to use tools because they did not have sharp teeth like other meat-eating animals, such as lions and tigers. Tools helped people to get food more easily.
Working with tools also helped to develop human intelligence. The human brain grew bigger, and human beings began to invent more and more tools and machines. The stone chip was one of the first tools that people used, and perhaps it is the mast important. Some scientists say that it was the key to the success of mankind.
Since 1960 a new kind of tool has appeared. This is the silicon chip—a little chip of silicon crystal. It is smaller than a finger-nail, but it can store more than a million "bits" of information. It is an electronic brain. Every year these chips get cleverer, but their size gets smaller, and their cost gets less. They are used in watches, calculators and intelligent machines that we can use in many ways.
In the future we will not need to work with tools in the old way. Machines will do everything for us. They will even talk and play games with us. People will have plenty of spare time.
选项
A、They made them by knives.
B、They found adequate stones.
C、They used bones of animals.
D、They made tools by hitting stone against stone.
答案
D
解析
How did people make tools two million years ago?
转载请注明原文地址:https://kaotiyun.com/show/H5ZK777K
0
大学英语六级
相关试题推荐
Ifyouarenow______,youneedtodomoreexercisestobuildyourbody.
Theyare______studentsthattheyallperformedwellinthefinalexaminations.
Alotofyoungpeoplefinditdifficulttogetajob,especiallyinthefirstfewmonthsaftertheyleaveschool.Thisismuchm
IntheUnitedStates,peoplemaygotodifferentshoppingplacesaccordingtotheireconomic【T1】______.Wealthypeopleoftengo
7October,2008HuaxiaIndustrialCorp.903MinhuaRoadGuangzhouP.R.ChinaAttention:Mr.AllenYoungSubject:RequestforAB
Nowthepollutioncausedbytheincreasingnumberofcars______moreandmoreseriousinmanycities.
A—accidentpreventionJ—emergencyresponseplanB—personalprotectiveequipmentK—worker’scompensationC—healt
MemoTo:Peter,DeputyEditorFrom:DanielThomas,Editor-in-chiefDate:June6,2014Subject:EnsuringsmoothpublicationofJu
MemoTo:Peter,DeputyEditorFrom:DanielThomas,Editor-in-chiefDate:June6,2014Subject:EnsuringsmoothpublicationofJu
Davidfoundthebookenlightening,it______(有很多关于这个学科的知识).
随机试题
下列关于注册会计师针对收入执行分析程序的做法中,正确的有()。
某给水系统水厂内设有清水池,管网内设有高位水池,给水系统的用水量变化曲线见下图1,水厂二级泵房供水量变化曲线见下图2,则管网中高位水池的有效容积为()m3。
在高倍数泡沫产生器的发泡网前小于或等于()处,不能有影响泡沫喷放的障碍物。
风险事件:2011年10月31日,拥有长达200年历史的世界最大期货交易商——全球曼氏金融控股公司(以下简称“全球曼氏金融”)向纽约南区破产法院提交了破产保护申请。相关背景:2010年3月,原新泽西州州长和高盛掌门人乔恩·克辛
下列关于细胞分化、衰老、凋亡和癌变的叙述,正确的是()。
比较巴洛克时期清唱剧和康塔塔的异同。
《周礼.秋官.小司寇》:“以五声听狱讼,求民情,一日辞听,二日色听,三日气听,四日耳听,五日目听。”郑玄疏:“观其出言,不直则烦;观其颜色,不直则赫然;观其气息,不直则喘;观其听聆,不直则惑;观其眸子,不直则吒然。”请运用中国法制史的知识和理论,分析上述材
求∫-22(3x+1)max{2,x2}dx.
A、 B、 C、 D、 E、 B
A、 B、 C、 A
最新回复
(
0
)