题干

如图,两只U型管中分别加入纯净、等物质的量的铝粉和铁粉,同时将两端注射器内的液体(等质量、浓度为20%的稀硫酸)快速注入U型管中。

 

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同类题1

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    All languages change over time, but some change at a faster rate than others. ____ The most important factors are the number of people who speak a language, where they live and whether they move around, the importance of the language for world trade and communication, and changes in technology.

    ____ However, today English is the most widely used language in the world. English is spoken by about 350 million people as a first language in countries such as Great Britain, the United States. In addition, about a billion more people speak English as a second language.

    English started to take over French as an international language during the period of British colonialism (殖民主义) when the English ruled many countries in Africa and Asia. ____ The colonial period came to an end at the same time that several other changes occurred. For example, the U.S. started to play a greater part in global affairs and the international economy. New means of communication technology such as television and the Internet spread English worldwide. ____ In addition, they could use the Internet for information, business, or e-mail communication, all in English. Just as the use of English spread, other languages changed English by contact or by new inventions and technology.

    In contrast, Icelandic is a language that has changed very slowly. Icelandic speakers today can understand poetry written in a slightly different dialect over 1,000 years ago! Why has Icelandic changed so slowly? The main reason is the isolated (孤立的) location of the island in the middle of the Atlantic Ocean. ____ Compared to England, Iceland had no history of colonialism. Iceland's small population has not played a major role in international trade or communication. Today, most Icelanders speak English in addition to their native language. With outside influences, Icelandic is changing more rapidly now.

A. People everywhere could watch the news or sports events in English.

B. These changes have a great influence on the development of society.

C. Isolation meant that for hundreds of years, Icelanders had little contact with speakers of other languages.

D. What are some of the factors that influence how quickly a language changes?

E. The language communication brings about the communication of technology.

F. In the past, other languages such as Latin or French were more important than English.

G. English was the primary means of communication in these colonies.

同类题5

阅读下列材料,回答问题。

材料一:“一带一路”是“丝绸之路经济带”和“21世纪海上丝绸之路”的简称。它将充分依靠中国与有关国家既有的双多边机制,借助既有的、行之有效的区域合作平台,一带一路旨在借用古代丝绸之路的历史符号,高举和平发展的旗帜,积极发展与沿线国家的经济合作伙伴关系,共同打造政治互信、经济融合、文化包容的利益共同体、命运共同体和责任共同体。

材料二:当今世界正发生复杂深刻的变化,国际金融危机深层次影响继续显现,世界经济缓慢复苏、发展分化,国际投资贸易格局和多边投资贸易规则酝酿深刻调整,各国面临的发展问题依然严峻。共建“一带一路”顺应世界多极化、经济全球化、文化多样化、社会信息化的潮流,秉持开放的区域合作精神,致力于维护全球自由贸易体系和开放型世界经济。共建“一带一路”旨在促进经济要素有序自由流动、资源高效配置和市场深度融合,推动沿线各国实现经济政策协调,开展更大范围、更高水平、更深层次的区域合作,共同打造开放、包容、均衡、普惠的区域经济合作架构。共建“一带一路”符合国际社会的根本利益,彰显人类社会共同理想和美好追求,是国际合作以及全球治理新模式的积极探索,将为世界和平发展增添新的正能量。

——以上材料摘自网易新闻