If you are looking for information, library shelves are a good place to start. But if you need up-to-the-minute data or have specialized needs, you may find a computerized database more useful, less expensive, and less time 11 .A database, a file of information on one subject or family of subjects, can be stored and 12 in a computers memory. The speed of the computer then 13 you to recall any item in this file almost 14
The three main types of databases are statistical, bibliographic, and full text. Statistical databases store 15 amounts of numerical data, such as wage and price indexes, census information, foreign 16 rates and bond prices. Bibliographic databases store references to and summaries of articles in periodicals and newspapers. Full-text databases offer the complex texts of such 17 as newspaper, magazine, and journal articles.
Thousands of databases exist today, and their numbers are growing. Many companies have their in-house database, which is 18 to employees through computer terminals or microcomputers. In addition, several hundred commercial databases are now available to the 19 , with literally millions of items of information readily obtainable. These databases 20 specific fields, such as law and financial forecasting, or general information, such as sports and weather data.
A. exchange B. public C. instantly D. cover
E. enables F. consuming G. remained H. materials
I. hide J. intensively K. vast L. communications
M. exhausting N. accessible 0. maintained
II. F 12. O 13. E 14. C 15. K 16. A 17. H 18. N 19. B 20. D
新四级听力的听写练习第二单元 Lesson 5
新四级听力的听写练习第一单元 Lesson 15
英语四级听力短对话模拟训练第19套
英语四级听力短对话模拟训练第8套
英语四级听力短对话模拟训练第15套
新四级听力的听写练习第一单元 Lesson 2
新四级听力的听写练习第二单元 Lesson 2
英语四级听力长对话模拟训练第21套
英语四级听力短对话模拟训练第26套
新四级听力的听写练习第二单元 Lesson 13
英语四级听力短对话模拟训练第7套
英语四级听力短对话模拟训练第14套
新四级听力的听写练习第一单元 Lesson 4
英语四级听力短对话模拟训练第18套
英语四级听力短对话模拟训练第5套
英语四级听力短对话模拟训练第3套
英语四级听力短对话模拟训练第20套
英语四级听力短对话模拟训练第23套
新四级听力的听写练习第一单元 Lesson 24
英语四级听力短对话模拟训练第17套
新四级听力的听写练习第一单元 Lesson 17
新四级听力的听写练习第一单元 Lesson 6
新四级听力的听写练习第三单元 Lesson 6
新四级听力听写练习第一单元Lesson 1
英语四级听力短对话模拟训练第22套
英语四级听力短对话模拟训练第24套
新四级听力的听写练习第一单元 Lesson 21
新四级听力的听写练习第二单元 Lesson 1
新四级听力的听写练习第一单元 Lesson 20
新四级听力听写练习第二单元 Lesson 16
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