首页
登录
职称英语
[img]2016m12s/ct_eyyjscz2015j_eyyjsccloze_0151_201611[/img] Diamond is the h
[img]2016m12s/ct_eyyjscz2015j_eyyjsccloze_0151_201611[/img] Diamond is the h
游客
2023-10-17
19
管理
问题
Diamond is the hardest naturally occurring substance known. It is the most popular gemstone and because of its extreme 【C1】______(hard), it is also used for various industrial purposes. Scientists are still 【C2】______(sure)of the exact process by which diamonds are naturally formed, but it is certain that both extreme heat and enormous pressure are needed. It is, therefore, likely that diamonds were formed far【C3】be______the Earth’s surface where these conditions exist. The first synthetic diamonds were successfully produced in the 1950s, but the best and largest stones are still those created by nature.
The word ’ diamond’ comes from the Greek ’ adamas’ , which means invincible, but the first definite reference to diamonds occurs in Roman literature of the first century A. D. The diamonds known to the Romans came from India, which was the only 【C4】______(supply)of the stones until the eighteenth century. In 1762, diamonds were discovered in Brazil, and then in 1866 in South Africa, the main source of diamonds in the world today.
The idea that men should give diamonds to the women they 【C5】______is quite new. It was invented in the last century by De Beers, the company that owns the South African diamond mines. The idea that ’diamonds are forever’ does not hold water either. Although diamonds are very hard, they can be【C6】dam______.
The largest of all known diamonds was the Cullinan. It was【C7】disc______in South Africa in 1905 and given to Edward VII, king of Great Britain. It was cut into smaller stones, the largest of which—and still the largest cut diamond in 【C8】______(exist)—is called the Star of Africa.
There have been a lot of diamond thefts in recent years, but scientists can now mark stones to show who own them. Usually this mark is 【C9】______(visible), so thieves can’t tell if a diamond is marked. 【C10】O______the people who know how to make the mark appear can tell whether a diamond is marked or not. [br] 【C8】
选项
答案
existence
解析
(该句的句意为“它被切割成小的钻石,其中最大的那颗仍然是现存的最大的切钻”,inexistence表示“现存的;现有的”。)
转载请注明原文地址:https://tihaiku.com/zcyy/3105803.html
相关试题推荐
[img]2016m12s/ct_eyyjsdm_eyyjsdreadb_0064_201612[/img]【B1】______Manyofthe
[img]2016m12s/ct_eyyjsdm_eyyjsdreadb_0064_201612[/img]【B1】______Manyofthe
[img]2016m12s/ct_eyyjsdm_eyyjsdreadd_0076_201612[/img]Certainbirdsare,mo
[img]2016m12s/ct_eyyjsdm_eyyjsdreadd_0076_201612[/img]Certainbirdsare,mo
[img]2016m12s/ct_eyyjsdm_eyyjsdreadd_0076_201612[/img]Certainbirdsare,mo
WaterforLife[img]2016m12s/ct_eyyjsdm_eyyjsdcloze_
WaterforLife[img]2016m12s/ct_eyyjsdm_eyyjsdcloze_
WaterforLife[img]2016m12s/ct_eyyjsdm_eyyjsdcloze_
WaterforLife[img]2016m12s/ct_eyyjsdm_eyyjsdcloze_
WaterforLife[img]2016m12s/ct_eyyjsdm_eyyjsdcloze_
随机试题
TheHistoryofChineseAmericans[A]Chinesehavebee
实行备案制的企业投资项目,由企业自主决策,按照( )原则,企业应当在开工建设前
正常新生儿脾脏为A.左肋下不能扪及 B.左肋下0.5cm内 C.左肋下1~2
男性,60岁,诊断为甲状腺功能减退症,要鉴别原发性、垂体性和下丘脑性甲减,需做哪
哈尔滨某商场工程,地上2层,地下1层,建筑面积4210㎡。筏板基础,混合结构,现
HOAP方案常用于治疗( )。A.急性粒细胞白血病 B.急性淋巴细胞白血病
在水平均质具有潜水自由面的含水层中进行单孔抽水试验如图7-20所示,已知水井半径
下列矿物按照硬度从低到高排序正确的是:①金刚石②刚玉③石英④石膏A.④③②①
张某犯了A罪,根据我国刑法规定:犯A罪的,“处三年以下有期徒刑、拘役或者管制,并
甲状腺功能减退症的最主要表现是 A.体重减轻 B.畏寒便秘 C.性欲减退
最新回复
(
0
)