问答题

The information in many databases consists of natural-language texts of documents. Information is retrieved from these computerized records based on the presence in them of words or short phrases that are identical to those posed in the user’s query. In a typical query, the user provides a sequence of characters, such as the title of a journal or the name of a subject area, and the computer searches in the database for a corresponding sequence of characters and provides the source materials in which those characters appear. Queries are the principal means by which users retrieve database information.

【参考答案】

数据库是指为了更快查询和获取信息而专门组织的数据资料收集，这一收集通常是由电脑完成的。数据库以易于数据的获取、操作、删除......

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During the 20th century Europe has experienced periods of considerable economic growth and prosperity, and industrial development has proliferated much more widely throughout the continent: but continued economic development in Europe has been handicapped to a large degree by its multi- national character--which has spawned economic rivalries among states and two devastating World wars--as well as by the exhaustion of many of its resources and by increased economic, competition from overseas. Governmental protectionism, which has tended to restrict the potential market for a product to a single country, has deprived many industrial concerns of the efficiencies of large-scale production serving a mass market ( such as is found in the United States). In addition, enterprise efficiency has suffered from government support and from a lack of competition within a national market area. Within individual countries there have been growing tensions between regions that have prospered and those that have not. This core-periphery problem has been particularly acute in situations where the contrasting regions are inhabited by different ethnic groups.
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Every human society has its own particular culture, or sociocultural system, which overlaps to some extent with other systems. Variation among sociocultural systems is attributable to physical habitats and resources; to the range of possibilities inherent in various areas of activity, such as language, rituals and customs, and the manufacture and use of tools, and to the degree of social development. Adaptation and change take place within and among cultures by means of ecological and environmental changes.
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