Passage One
Electronic computers are amongthe fastest and most useful instruments for sorting and comparing in use today.Computers provide means for greater speed and accuracy in working with ideasthan had previously been possible. With the development of these new tools, itis as if man has suddenly become a millionaire of the mind.
Although man has been growingmentally richer ever since he started to think, the electronic computer allowsand will continue to allow him to perform tremendous mental tasks in arelatively short time. Great scientists of the past produced ideas which werethe basis for great advances, but their ideas sometimes had to wait for yearsbefore they were understood sufficiently well to be of practical use. With thecomputer，theideas of today’s scientists can be studied, tested, distributed, and used morerapidly than ever before.
Old lines and methods ofcommunication do not work easily or efficiently with as much information as wehave now. The repeated actions of preparing, sorting, filling, distributing,and keeping track of records and publications can be as troublesome ascalculating. Errors occur because men grow tired and can be distracted.
The basic job of computers isthe processing of information. For this reason computers can be defined asdevices which accept information, perform mathematical or logical operationswith the information, and then supply the results of these operations as newinformation.
Although a sharp dividing linebetween types of computers is not always easy to see, computers are usuallydivided into two broad groups：digital and analog. Digital computers work by using specificinformation which is usually in the form of numbers. Analog computers, on theother hand, usually process continuous information.
To explain the differences,let us consider two devices which handle information in a manner similar to thetwo types of computers. A turnstile, which has a counter attached to it, canhelp to explain the way a digital computer works. Each time a person passesthrough the turnstile, the indicator quickly jumps from one number to another.Each number registered is separate and specific.
The continuous change in thelevel of sand in an hourglass as time passes makes it an analog device. Perhapsthe first analog computation was the use of graphs for the solution ofsurveying problems.
According to the passage, computers are mainly used to do the following except____.
A、performingmath operations
B、processing information
C、supplying solutions
D、storing technical data
【正确答案】：C
【题目解析】：细节判.断题。本题可以从第3段和第4段得到正确选项。C项发生了错位现象，它不是电脑的主要用途。答案为C。