更多
首页 - 网校 - 万题库 - 美好明天 - 直播 - 导航 -
您现在的位置: 考试吧 > 英语四六级考试 > 学习资料 > 英语四级 > 阅读 > 正文

2020年大学英语四级阅读练习:地层

来源:考试吧 2020-5-29 11:47:11 要考试,上考试吧! 英语四六级万题库
考试吧整理“2020年大学英语四级阅读练习:地层”,更多英语四级阅读习题,请访问考试吧英语四六级考试网或微信搜索“万题库英语四六级考试”。

 

  The Earth comprises three principal layers: the dense, iron-rich core, the mantle made of silicate (硅酸盐) that are semi-molten at depth, and the thin, solid-surface crust There are two kinds of crust, a lower and denser oceanic crust and an upper,lighter continental crust found over only about 40 percent of the Earth's surface. The rocks of the crust are of very different ages. Some continental rocks are over 3,000 million years old, while those of the ocean floor are less than 200 million years old. The crusts and the top, solid part of the mantle, totaling about 70 to 100 kilometers in thickness, at present appear to consist of about 15 rigid plates, 7 of which are very large. These plates move over the semi-molten lower mantleto produce all of the major topographical(地形学的)features of the Earth. Active zones where intense deformation occur are confined to the narrow, interconnecting boundaries of contact of the plates.

  There are three main types of zones of contact: spreading contacts where plates move apart, converging contacts where plates move towards each other, and transform contacts where plates slide past each other. Newoceanic crust is formed along one or more margins of each plate by material issuing from deeper layers of the Earth' s crust, for example, by volcanic eruptions (爆发) of lava (火山熔岩) at mid-ocean ridges. If at such a spreading contact the two plates support continents,a rift(裂缝) is formed that will gradually widen and become flooded by the tea. The Atlantic Ocean formed like this as the American and Afro-European plates moved in opposite directions. When two plates carrying continents collide, the continental blocks,too light to be drawn down, continue to float and therefore buckle (起褶皱) to form a mountain chain along the length of the margin of the plates.

  练习题:

  Choose correct answers to the question:

  1.The Earth’s crust______.

  A.can be classified into two types

  B.is formed along the margins of the plates

  C.consists of semi-molten rocks

  D.is about 70 to 100 kilometers thick

  2.The 15 plates of the Earth are formed from ___.

  A.the oceanic crusts and continental crusts

  B.the crusts and the mantle

  C.the crusts and the top and solid part of the mantle

  D.the continental crusts and the solid part of the mantle

  3.Seriously-deformed zones appear _______

  A.whenever the crusts move over mantle

  B.when the plates move towards each other

  C.in the narrow boundaries where two plates meet

  D.to be the major topographical feature of the Earth

  4.According to the second paragraph, the formation of the Atlantic Ocean is the example of_______.

  A.spreading contacts

  B.the influence of volcanic eruptions

  C.converging contacts

  D.transform contacts

  5.This passage is probably_______.

  A.a newspaper advertisement

  B.a chapter of a novel

  C.an excerpt from a textbook

  D.a scientific report of new findings

  1.[A] 事实细节题。选项A与文章第1段第2句所述一致,为正确答案。此类题可采用排除法。根据第2段第2句的内容可以知道选项B所指的只是地壳中的一种.而不是所有地壳。选項C与文章第1句的内容不符。选項D的主语应该是地壳和上层的地幔,不仅仅是地壳。

  2.[C] 推理判断题。此题可定位到第1段倒数第3句。题干中的15 plates是原文该句中的宾语,且该句的谓语中心词是consist of(由......组成),题干的谓语是are formed from,这意思一致,但题目用的是被动语态。表明答案可从原文该句的主语得到。主语中的top和solid并列修饰part of the mantle。选项C为该句的同义替换,故正确。

  3.[C] 亊实细节题。选项C是对第1段最后一句的同义改写。文章中没有提到选项A中the crusts move over mantle 这种现象;选项B提到的现象在第2段第1句才讨论到,与题干无关;文中也没有提到严重变形的地区是地球的主要地形特征,因此选项D不正确。

  4.[A] 亊实细节题。第2段主要分成两部分:第一部分谈板块活动的三种形式,第二部分分别举例说明其中在说明spreading contacts时,引用了大西洋的例子:"The Atlantic Ocean formed like this...",所以答案为A。

  5. [C] 主旨大意题。由本文的语言风格和描述内容可以判定这篇文章既不是商业性的,也不是文学性的同时文中叙述的内容具有科普性质,不可能是太前沿性的,因此A、B、D三项都不正确,选项C为此题答案。

扫描/长按二维码可帮助学习46级考试
了解四六级考试动态
了解四六级历年真题
了解四六级考试技巧
了解作文听力等资料

四六级万题库 | 微信搜索"万题库英语四六级考试"

  相关推荐

  2020英语四六级考试时间 | 英语四级作文 | 六级作文

  历年大学英语四级考试真题听力(含MP3)汇总

  历年大学英语四级真题及答案|解析|估分|下载

  历年大学英语六级真题及答案|解析|估分|下载

  历年大学英语六级考试听力下载(原文+MP3)汇总

  2020大学英语四级考试真题 | 英语六级考试真题答案

0
收藏该文章
0
收藏该文章
文章责编:zhangyuqiong  
看了本文的网友还看了
文章搜索
万题库小程序
万题库小程序
·章节视频 ·章节练习
·免费真题 ·模考试题
微信扫码,立即获取!
扫码免费使用
英语四级
共计423课时
讲义已上传
30206人在学
英语六级
共计313课时
讲义已上传
20312人在学
阅读理解
共计687课时
讲义已上传
5277人在学
完形填空
共计369课时
讲义已上传
13161人在学
作文
共计581课时
讲义已上传
7187人在学
推荐使用万题库APP学习
扫一扫,下载万题库
手机学习,复习效率提升50%!
版权声明:如果英语四六级考试网所转载内容不慎侵犯了您的权益,请与我们联系800@exam8.com,我们将会及时处理。如转载本英语四六级考试网内容,请注明出处。
精选6套卷
8次直播课
大数据宝典
通关大法!