首页
登录
职称英语
A scorching sun, an endless sea of sand and a waterless, forbiddingly lonely
A scorching sun, an endless sea of sand and a waterless, forbiddingly lonely
游客
2025-04-09
3
管理
问题
A scorching sun, an endless sea of sand and a waterless, forbiddingly lonely land—that is the image most people have of deserts. But how true is this picture? Deserts are dry lands where rainfall is low. This is not to say rain never falls in deserts: it may fall once or twice a year in a fierce torrent that fades almost as soon as it has begun, or which evaporates in the hot air long before it has got anywhere near the earth. It may fall in a sudden sweeping flood that carries everything in its path. Rains may only come once in five or six years or not fall for a decade or more. The Mojave desert in the United States remained dry for twenty-five years.
Without water no living thing can survive, and one feature of the true desert landscape is the absence of vegetation. With little rain and hardly any vegetation the land suffers under the sun. There are virtually no clouds or trees to protect the earth’s surface and it can be burning hot. Under the sun, soils break up and crack. Wind and torrential rain sweep away and erode the surface further. Eight million square kilo-meters of the world’s land surface is desert. Throughout history deserts have been expanding and re-treating again. Cave paintings show that parts of the Sahara Desert were green and fertile about 10,000 years ago, and even animals like elephants and giraffes roamed the land. Fossil and dunes found in fer-tile and damp parts of the world show that these areas were once deserts. But now the creation of new desert areas is happening on a colossal scale. Twenty million square kilometers, an area twice the size of Canada, is at a high to very high risk of becoming desert. With a further 1.25 million square kilometers under moderate risk, an area covering 30% of the earth’s land surface is desert, becoming desert, or in danger of becoming desert. The rate of growth of deserts is alarming. The world’s dry lands which are under threat include some of the most important stock-rearing and wheat-growing areas and are the homes of 600~700 million people. These regions are becoming deserts at the rate of more than 58,000 square kilometers a year or 44 hectares a minute. In North Africa at least 100,000 hectares of cropland are lost each year. At this rate there is a high risk that we will be confined to living on only 50% of this planet’s land surface within one more century unless we are able to do something about it. [br] In the sentence "an area covering 30% of the earth’s land surface is desert, becoming desert, or in danger of becoming desert" , the part of " is desert, becoming desert, or in danger of becoming desert" can be best replaced with____.
选项
A、is becoming desert, has become desert, or will becoming into desert
B、has been desert, is becoming desert, or will become into desert
C、is becoming desert, will become desert, or becomes into desert
D、has been desert, is becoming desert, or will become into desert
答案
D
解析
很明显,本句的意思是采用了“已经变成沙漠,正在变成沙漠和即将变成沙漠”的时间顺序。
转载请注明原文地址:http://tihaiku.com/zcyy/4033579.html
相关试题推荐
After______seemedanendlesswait,itwasherturntoenterthepersonnelmanage
Inspiteof"endlesstalkofdifference",Americansocietyisanamazingmac
Inspiteof"endlesstalkofdifference",Americansocietyisanamazingmac
Inspiteof"endlesstalkofdifference",Americansocietyisanamazingmach
Inspiteof"endlesstalkofdifference",Americansocietyisanamazingmach
Telephonessavethefeetandendlessamountsoftime.Thisisduepartlytothe
Ascorchingsun,anendlessseaofsandandawaterless,forbiddinglylonely
Ascorchingsun,anendlessseaofsandandawaterless,forbiddinglylonely
Ascorchingsun,anendlessseaofsandandawaterless,forbiddinglylonely
Howmuchpaindoanimalsfeel?Thisisaquestionwhichhascausedendlessc
随机试题
RunningonemptyArevolutionarynew
Ayoungster’ssocialdevelopmenthasaprofoundeffectonhisacademicprogr
不宜用于变异型心绞痛的药物是A.硝酸异山梨酯 B.维拉帕米 C.硝酸甘油
土地资源是指在一定的生产力水平下,在一定的技术条件和一定时间内,可被人们用于(
某银行将自己定位为客户“身边的银行…‘信赖的银行”,强调信誉实力和网点实力,符合
(2017年真题)甲和乙同为药品批发企业,其所持有的《药品经营许可证》载明的经营
在进行培训与开发需求分析时,组织分析的内容包括()。A.公司战略 B.
某汽车制造厂生产的小汽车应按自产自用缴纳消费税的有( )。A.用于本厂研究所作
(2017年真题)下列各项中,应当进行追溯调整会计处理的是( )。A.分类为权
所有者权益与负债都是企业资产的来源。
最新回复
(
0
)