I/O Devices of Computer输入输出设备（双语解释）

  Keyboard: A keyboard is an input device of a computer. Through a keyboard, English letters, numbers and punctuation can be inputted into the computer, so keyboards can say the words. What’s more, we can input data to the computer via it.
Although different computers have different styles of keyboards, they generally composed of four components: typewriter keys, function keys, control keys, and digital small keyboard.
    键盘是计算机一种输入设备。通过键盘，可以将英文字母、数字、标点符号输入到计算机中，因而可以向计算机发出命令。而且我们可以通过它向计算机输入数据。
纵使不同类型的计算机有不同类型的键盘，它们都由四个部分组成：打字机键，功能键，控制键，数字小键盘。

  A mouse is an input device used most commonly besides keyboard. When you move the mouse, it will transfer the signal to the computer through its tail and tell its moving direction to it. For example, when you move the mouse to the left, the arrowhead on the screen will also move in the direction of the left. In addition, if you take the mouse in the space, the arrowhead on the screen will not move in the same direction, only waiting doubtfully for what you are doing.
Mouse is not only interesting, but also useful. For example, in Windows XP, there are many programs using the “buttons”. When moving the arrowhead on the screen to the graphic with the “button” and pressing the mouse’s left, you will give computer some orders to perform some tasks.
    鼠标是除键盘之外最常用的输入设备。当你移动鼠标时，它会通过尾巴把信号发送给计算机，并且告诉它的移动方向。例如，当你把鼠标向左移动时，屏幕上的箭头也会向左移动。此外，若你把鼠标拿到空中移动时，箭头将不会随着同样的方向移动，仅怀疑你在做什么。
鼠标不但很有趣，也很有用。例如，在Windows XP中，有很多使用“按钮”的程序，当你把屏幕上的箭头移动到画着“按钮”的图形上面并按鼠标左键时，你就向计算机发出完成某些任务的指令。

  Monitor is an important output device of a computer, whose purpose is to display the data in the computer by means of letters and graphics. Its characteristics include fast speed, noiselessness, convenient usage and display multiplicity, etc. its shortcomings are only to look, but not to print out. At present, two types of monitors are available: LCD and CRT.
  Monitor is one part of a video system. In practice, the video system consists of a monitor and a display adapter. The monitor is outside the computer mainframe. On the monitor, there are some knobs which are used to adjust its lightness, contrast, color and the screen’s size and location, etc.
   显示器是计算机的重要输出设备,其作用是将计算机数据以文字和图表的方式显示出来。它的特点包括速度快，无噪声，使用简便和显示多样性等。缺点是仅能看，不能打印输出。目前有两种类型的显示器可使用：液晶显示器和CRT显示器。
   显示器是视屏系统的一部分。实际上，视屏系统由显示器和显示适配器组成。显示器在主机的外部。有一些旋钮在上面，用来调节显示器亮度，对比度，颜色以及屏幕大小和位置等。 

  Printer is another important output device of a computer. In general, after the driver is set, printer will realize the printout with the support of certain software. Therefore, the use of the printer is very simple. At present, the printers used most commonly are wire printers, inkjet printers, and laser printers. 
  Wire printers: Wire printer is also referred to as lattice printer. It carries out printing by styluses on the head of printer through the ribbon, thereby forming some lattices composed of characters and graphics.
  Inkjet printers: Inkjet printer spills the sprinkled ink smudge on the different position of paper, thereby forming various characters and graphics.
  Laser printers: Laser printer’s principle is similar to copycat. However, it does not use the common lamp-house but the laser.
  打印机是计算机另一个重要的输出设备。通常，设置好驱动程序后，打印机即可在某种软件支持下实现打印输出。因此，打印机的使用很简单。目前最常用的打印机有针式打印机、喷墨打印机和激光打印机。
  针式打印机：也被称为点阵打印机，它是由打印头上的钢针经过色带在纸上打印，形成一些点阵组成的字符和图像。
  喷墨打印机：将喷出的墨点落在纸上的不同位置，形成各种字符和图像。
  激光打印机：原理类似于复印机。然而，它使用激光而不是普通电源。

Key words & Expressions:
Punctuation: n.标点符号
Component: n.组成成分
Typewriter: n.打字机
Arrowhead: n.箭头
Adaptor: n.适配器
Lightness: n.亮度
Wire printer: n.针式打印机
Ink-jet printer: n.喷墨打印机
Laser printer: n.激光打印机
Lattice: n.点阵
Ribbon: n.色带
Copycat: n.复印机