11. 光缆 fiber-optic cable 12. 传真机 fax machine
13. 无线通信 wireless communications
14. 点对点通信 point-to-point communications 15. 调制电脉冲 modulated electrical impulse 16. 通信卫星 communication(s) satellite 17. 电报电键 telegraph key
18. 传输媒体 transmission medium (或media) 19. 无绳电话 cordless telephone 20. 金属导体 metal conductor
III. Fill in each of the blanks with one of the words given in the following list, making changes if necessary:
Data communications is the process of transmitting and receiving data in an orderly way
so the data that arrives at its destination is an accurate duplication (复制) of the data that was sent. When data travels a short distance, such as when you send data from your computer to
your printer, it is referred to as local communications. When data travels a long distance, the
communication is referred to as telecommunications; the prefix (前缀) “tele” is derived from a Greek word that means “far” or “far off.” The difference between a short distance and a long distance is somewhat arbitrary (武断
的). For example, if your computer sends data to a printer in the next room, it is regarded as
local communications; if you phone the person in the next room, you are transmitting data
over a telecommunications device. However, the same basic communications concepts apply
to both local communications and telecommunications.
Basic data communications concepts are the building blocks for understanding how data
travels on a communications system. These concepts come in handy (派得上用处) when you
install, configure, or upgrade a local area network. In addition, these concepts help you set up modems, fax machines, and cellular data transfers. IV. Translate the following passage from English into Chinese:
个人计算机使用电信来提供传输链路，用于传送音频、视频、文本、软件和多媒体
服务。许多专家认为，这些服务 的结合将带来用户对新一代高速、宽带网络的需求。当
前，这些音频、视频和文本服务大多通过现有的电话连接使用因特网传送。有些计算机
使 用综合业务数字网或数字用户线路直接连接到电话网的数字部分，但这要求在用户处
有专门的设备。此外，电话及有线电视公司还必须对其线路进行 升级，以使其能够进行
高速数据传输。在许多地点，有高速数据传输需求的公司和个人现在可选择从电话公司
得到数字用户线路服 务，从有线电视公司得到光缆调制解调器服务。
Unit Seven/Section B
I. Fill in the blanks with the information given in the text:
1. controller 2. main; CPU 3. digital; voice
4. parallel; serial或serial; parallel
II. Translate the following terms or phrases from English into Chinese and vice versa: 1. bit map 位图，位映象 2. parallel port 并行端口
3. direct memory access (DMA) 直接存储器存取 4. universal serial bus 通用串行总线 5. general-purpose register 通用寄存器 6. 电路板 circuit board
7. 串行通信 serial communication 8. 数码照相机 digital camera
9. 存储映射输入/输出 memory-mapped I/O 10. 有线电视 cable television Unit Seven/Section C
I. Fill in the blanks with the information given in the text: 1. Transfer 2. cells 3. label 4. integrated