例题2 　　1、先看文章后面的问题，找出每一句题干中的关键词，特别关注时间、地点、专有名词、关键动词以及表示上下文逻辑关系的单词或者短语。 　　2、回到原文，阅读原文，按照题目顺序作答。 　　3、观察文章题目和每一段的第一句话，找出本段的主题句。 　　4、在阅读文章时，看到题干中的关键词或者同题干关键词相同或相近的单词或短语时，要特别留意。 　　5、注意区分“错误(wrong)”和“没有提到(not mentioned)”。 　　Computer Mouse 　　The basic computer mouse is an amazingly clever invention with a relatively simple design that allows us to point at things on the computer 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 computer mouse daily without stopping to think how it works (第一题：大多数大多数计算机用户天天使用计算机，却没有想到要了解以下鼠标的工作原理。选择“B错误”)until it gets dirty and we have to learn how to clean it. We learn to point at things before we learn to speak, so the mouse is a very natural pointing device. Other computer pointing devices include light pens, graphics tablets and touch screens, but the mouse is still our workhorse. 　　The computer mouse was invented in 1964 by Douglas Englehart of Stanford University. As computer screens became more popular and arrow keys were used to move 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 computer in 1983, really started the computer public on the road to relying on the mouse for routine computer tasks. 　　How does the mouse work? We have to start at the bottom, so think upside down 　　now. It all starts with the mouse ball(一切都始于鼠标球). As the mouse ball in the bottom of the mouse rolls over the mouse pad(当鼠标底部的鼠标球在鼠标垫上滚动的时候), it presses(压迫) against and turns two shafts(它压迫到两个滚轴并使其转动). The shafts are connected to wheels with several small holes in them(这两个滚轴上有一些小孔：“them”指的是“shafts”，并与滚轴相连). The wheels have a pair of small electronic light-emitting devices called light-emitting diodes (LED) mounted (fixed安装;固定) on either side. (滚轮两边各有一个叫做“二极管”的小型电子发光器件。)One LED sends a light beam to the LED on the other side.(其中一个发光的二极管向另外一个二极管发出光束。)(第四题：鼠标的部件有滚动部件，如滚球，也有观点装置，如二极管等。二极管将光信号转换为电信号，传送到计算机，计算机根据收到的电信号作出相应的反应，因此二极管是鼠标的主要部件，而滚轮等只是辅助性的机械部件。) As the wheels spin and a hole rotates by, the light beam gets through the LED on the other side. (当滚轮转过一个小孔时，光束通过小孔到达另一边的发光“二极管”。)But a moment later the light beam is blocked until the next hole is in place.(但是稍后，该光速被阻碍，知道下一个孔转到这个位置时才能继续通过，并到达另一边的发光“二极管”。) The LED detects a changing pattern of light(发光二极管检测出光束的变化模式), converts the pattern into an electronic signal(将该模式转换成电子信号，并通过一条伸出鼠标的电缆将信号传输给计算机。), and sends the signal to the computer through wires in a cable that goes out of the mouse body. This cable is the tail that helps give the mouse its name.(第三句：鼠标的名称源自鼠标主体拖出的一根看上去像老鼠尾巴一样的电线) The computer interprets the signal to tell it where to position the cursor(光标) on the computer screen. (计算机通过解读信号确定光标在计算机屏幕上的位置。) 　　So far we have only discussed the basic computer 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 dirt. Eventually you have to clean the mouse. (第五题：鼠标脏了，可以擦干净再用，并不需要更换。)The newer optical mice avoid this problem by having no moving parts. (第七题：新的光电鼠标因为没有滚动的部件，于是就避免了这一问题。光电鼠标因为没有普通鼠标使用的滚动部件，所以不会吸附灰尘，用不着擦拭，这是一种新型的鼠标。)