首页
登录
职称英语
63. The investigation of the accident lasted for almost two years. Sand: as
63. The investigation of the accident lasted for almost two years. Sand: as
游客
2023-10-19
39
管理
问题
63. The investigation of the accident lasted for almost two years.
Sand: as children we play on it and as adults we relax on it. It is something we complain about when it gets in our eye on a windy beach, and praise when it is made into sand castles.
But we don’t often look at it. If we did, we would discover an account of a geological past and a history of sea life that goes back thousands and, in some cases, millions of years.
Sand covers not just seashores, but also ocean beds, deserts and mountains.
64.______
And it is a major element in manufactured products too—concrete is largely sand, while glass is made of little else.
65______
Well, it is larger than fine dust and smaller than shingle. In fact, according to the most generally accepted scheme of measurement, grains can be called sand if their diameter is greater than 0. 06 of a millimetre and less than 0. 6 of a millimetre.
Depending on its age and origin, a particular sand can consist of tiny stones or porous grains through which water can pass.
66 ______
They have come from the breaking down of rocks, or from the dead bodies of sea creatures, which collect on the bottom of the oceans, or even from volcanic eruptions.
67 ______
If it is a dazzling white, its grains may come from nearby coral, from crystalline quartz rocks or from gypsum, like the white sand of New Mexico. On Pacific Islands, jet black sands form from volcanic minerals. Other black beaches are magnetic and are mined for iron ore.
68______
It washes rock into streams and rivers and down to the sea, leaving behind softer materials. By the time it reaches the sea, the hardest rocks remain but everything else has been broken into tiny particles of 0. 02 millimetre diameter or less. The largest pieces fall to the bottom quickly, while smaller particles float and settle only slowly in deeper water, which is why the sandy beach on the shoreline so often turns to mud further out.
69______
If the individual fragments still have sharp edges, you can be sure they were formed fairly recently. This is the case on the island of Kamoama in Hawaii, where a beach was created after a volcanic eruption in 1990. Molten lava spilled into the sea and exploded into glassy droplets.
It seems that when the poet William Blake saw infinity in a grain of sand he was not far wrong.
70____
Sand is an irreplaceable industrial ingredient which has many uses.
Sand cushions our land from the force of the sea, and geologist say it often does a better job protecting our shores than the most advanced coastal technology.
A. These may have the shape of stars or spirals, their edges rough or smooth.
B. It is one of the most common substances on earth.
C. In addition, it has one vital function which you might never even notice.
D. Rain is all important force in the creation of beaches.
E. In the great slow cycle of the earth, sand that was once rock can turn to rock again.
F. What exactly is sand?
G. Colour is another clue to the origins of sand.
H. It can be difficult to date the sand on a beach accurately but it is possible to get a general idea of whether or not the sand is "young”or "old". [br]
选项
答案
D
解析
这一段讲沙滩是如何形成的,本段最后一句指出which is why the sandy beach on the shore line so often turns to mud further out。
转载请注明原文地址:https://tihaiku.com/zcyy/3111810.html
相关试题推荐
Peoplehavebeenpaintingpicturesforatleast30,000years.Theearliestp
Peoplehavebeenpaintingpicturesforatleast30,000years.Theearliestp
Itoftenhappensthatanumberofapplicantswithalmostidenticalqualifica
Itoftenhappensthatanumberofapplicantswithalmostidenticalqualifica
Itoftenhappensthatanumberofapplicantswithalmostidenticalqualifica
Beggarscanbeseenonthestreets,subwayorat【C1】________spotsinalmost
Beggarscanbeseenonthestreets,subwayorat【C1】________spotsinalmost
Beggarscanbeseenonthestreets,subwayorat【C1】________spotsinalmost
Beggarscanbeseenonthestreets,subwayorat【C1】________spotsinalmost
Beggarscanbeseenonthestreets,subwayorat【C1】________spotsinalmost
随机试题
Ihavehadagreatdealoftrouble______(跟上班里其他同学).(in)keepingupwiththerest
A—enginefuelsystemJ—one-waydriveB—lightsandwiresK—h
Readinginvolveslookingatgraphicsymbolsandformulatingmentallythesou
[originaltext]W:Ourbedroomneedscleaning.Shallwecleanitnow?M:Thanky
[originaltext]W:Mr.Johnson,haveyouheardthemorningnewsreport?Millhas
Readthefollowingtext.Choosethebest
A. B. C. D.
(2017年真题)地基处理常采用强夯法,其特点在于()。A.处理速度快、工
女,43岁。发热、咳嗽、少量脓痰2周,既往健康。查体未见明显异常。血常规大致正常
按照法律规定,下列各选项中属于民事法律行为成立要件的有()。A.行为人意思
最新回复
(
0
)