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
Every geologist is familiar with the erosion cycle. No sooner has an area of land been raised alive sea-level than it becomes s
Every geologist is familiar with the erosion cycle. No sooner has an area of land been raised alive sea-level than it becomes s
admin
2013-11-29
94
问题
Every geologist is familiar with the erosion cycle. No sooner has an area of land been raised alive sea-level than it becomes subject to the erosive forces of nature. The rain beats down on the ground and washed【51】the finer particles, sweeping them into rivulets and then into rivers and out to sea. The frost freezes the rain water in cracks of the rocks and breaks【52】even the hardest of the constituents of the earth’s crust. Blocks of rock dislodged at high levels are brought down by the force of gravity. Alternate heating and【53】of bare rock surfaces causes their disintegration. In the dry regions of the world the wind is a powerful force in removing material from one area to another. All this is natural. But nature has also provided certain defensive forces. Bare rock surfaces are in【54】course protected by soil itself dependent initially on the weathering of the rocks. Slowly【55】surely, different types of soil with differing "profiles" evolve the main types depending primarily on the climate. The protective soil covering, once it is formed, is held together by the growth of vegetation. Grass and herbaceous plants,【56】long, branching tenuous roots, hold firmly together the surface particles. The【57】is true with the forest cover. The heaviest tropical down- pours beating on the leave of the giant trees reach the ground only【58】spray, gently watering the surface layers and penetrating along the long passages provided by the roots to the lower levels of the soil. The soil, thus protected by grass, herb, or trees, furnishes a quiet habitat for a myriad varied organisms-earth-worms that importantly modify the soil, bacteria, active in their work of converting【59】leaves and decaying vegetation into humus and food for the growing plants. Chemical action is constantly taking【60】. Soil acids attack mineral particles and salts in solution move from one layer in the soil to another.
选项
答案
but
解析
意思为“尽管很慢,但很确定”。
转载请注明原文地址:https://kaotiyun.com/show/xmhO777K
0
考博英语
相关试题推荐
Oldpeoplearealwayssayingthattheyoungpeoplearenot【51】theywere.Thesamecommentis【52】fromgenerationtogenerationan
Oldpeoplearealwayssayingthattheyoungpeoplearenot【51】theywere.Thesamecommentis【52】fromgenerationtogenerationan
Oldpeoplearealwayssayingthattheyoungpeoplearenot【51】theywere.Thesamecommentis【52】fromgenerationtogenerationan
Oldpeoplearealwayssayingthattheyoungpeoplearenot【51】theywere.Thesamecommentis【52】fromgenerationtogenerationan
Oldpeoplearealwayssayingthattheyoungpeoplearenot【51】theywere.Thesamecommentis【52】fromgenerationtogenerationan
Afterseveralnucleardisasters,a______hasragedoverthesafetyofnuclearenergy.
ItriedtorelaxbecauseIknewIwoulduseupmyoxygensooner____.
Theevolutionofsexratioshasproduced,inmostplantsandanimalswithseparatesexes,approximatelyequalnumbersofmalesa
Stratford-on-Avon,asweallknow,hasonlyoneindustry—WilliamShakespeare—buttherearetwodistinctlyseparateandincre
Stratford-on-Avon,asweallknow,hasonlyoneindustry--WilliamShakespeare--buttherearetwodistinctlyseparateandincreas
随机试题
以下选项中,能用作用户标识符的是( )。
慢性支气管炎病人的痰常为肺梗死病人的痰常为
食管癌患者有持续性胸背痛。表明
RNA是
磷脂酶A的作用激肽酶的作用
李先生于2007年1月采用分期付款方式购买了一套商品房,他根据房产分户图选择了一套两居室,并向商业银行申请了50万元抵押贷款,分10年按月等额还款。房子买好后,李先生对房子进行了装修,拆除了餐厅与厨房之间的非承重墙,增大了厨房的空间。李先生为单身,搬入新居
大华公司采用应收账款余额百分比法计提坏账准备,2005年初应收账款余额为158万元,坏账准备的余额为1.58万元,本期发生实际坏账3.2万元,收回以前的坏账1.1万元,2005年末应收账款余额为234万元,其中应收宇兴公司的50万元应收账款,因其经营困难,
下列关于股份支付的会计处理表述中,正确的有()。
工商行政管理的目标中,市场经济秩序的内涵包括()。
国家最大的零售商们报道:过去的6个月是销售旺季,但是在这个销售旺季,利润却比通常要低,这是不寻常的,因为通常而言,当销售增加时,利润也增加。下列哪一项,假如在过去6个月正确,最有助于解释上面所描述的不寻常现象?
最新回复
(
0
)