Computer mouse

　　The basic #puter mouse is an amazingly clever invention with a relatively simple design that allows us to point at things on the #puter and it is very productive. Think of all the things you can do with a mouse like selecting text for copying and pasting, drawing, and even scrolling on the page with the newer mice with the wheel. Most of us use the #puter mouse daily without stopping to think how it works until it gets dirty and we have to learn how to clean it. We learn to point at thing before we learn to speak, so the mouse is a very natural pointing device. Other #puter pointing devices include light pens, graphics tablets and touch screen, but the mouse still our workhorse.

　　The #puter mouse was invented in 1964 by Douglas Englehart of Stanford University. As #puter screens became popular and arrow keys were used to more around a body of text, it became clear that a pointing device that allowed easier motion through the text and even selection of text would be very useful. The introduction of the mouse, with the Apple Lisa #puter in 1983, really started the #puter public on the road to relying on the mouse for routine #puter tasks.

　　How does the mouse work? We have to start at the bottom, so think upside down for now. It all starts with mouse ball. As the mouse ball in the bottom of the mouse rolls over the mouse pad, it presses against and turns two shafts. The shafts are connected to wheels with several small holes in them. The wheels have a pair of small electronic light-emitting devices called light emitting diodes (LED) mounted on either side. One LED sends a light beam to the LED on the other side. As the wheels spin and a hole rotates by, the light beam gets through to the LED on the other side. But a moment later the light beam is blocked until the next hole is in place. The LED detects a changing pattern of light, converts the pattern into an electronic signal, and sends the signal to the #puter through wires in a cable that goes out the mouse body. This cable is the tail that helps give the mouse its name. The #puter interprets the signal to tell it where to position the cursor on the #puter screen.

　　So far we have only discussed the basic #puter mouse that most of you probably have or have used. One problem with this design is that the mouse gets dirty as the ball rolls over the surface and picks up the dirt. Eventually you have to clean your mouse. The newer optical mice avoid this problem by having no moving parts.

　　1. Most #puter users want to know how the #puter mouse works.

　　A. right B. wrong C. not mentioned

　　2. According to the author, general #puter users need not know how the #puter mouse was invented.

　　A. right B. wrong C. not mentioned

　　3. The #puter mouse derives its name from the cable that goes out its body, which looks like the tail of a mouse.

　　A. right B. wrong C. not mentioned

　　4. The key #ponents of a #puter mouse are the two LEDs.

　　A. right B. wrong C. not mentioned

　　5. When an ordinary #puter mouse gets dirty, it has to be replaced with a new one.

　　A. right B. wrong C. not mentioned

　　6. The most durable #puter mice on sale are the IBM ones.

　　A. right B. wrong C. not mentioned

　　7. The optical mouse is superior to the basic one in that the former has no moving parts.

　　A. right B. wrong C. not mentioned

　　答案与解析：

　　1.分析文章标题： Computer mouse (鼠标)

　　2.直接解题：

　　1. Most #puter users(使用者) want to (想要...)know how the #puter mouse (电脑鼠标)works(工作) .

　　A. right B. wrong C. not mentioned 

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