1. Unit 5 Computer Memory

2. Answer the following questions:  How many types of storage are mentioned in the passage?  What is the most important advance in computer memory?  Which type is the one recommended for the secondary storage for NC?  What is the CPU’s main job?

3. Notes:  Refer to 指代, 涉及  Associate with 与 … 有联系  Mislead 误会, 误解  Systematic 系统的  At least 至少  Preferably 最好  Classify 划分  Primary 主要的, 首要的  Secondary 次要的, 辅助的  Amazing 令人惊讶的  Reliable 可靠的

4.  Recommend 推荐  Bubble 泡  More than  Adequate 适合于  Function 功能  Element 部分, 组成元件  Temporary 暂时的  Demand 需求  All aspects of … 的各个方面  Error 错误, 误差

5. Translate the following sentences:  Computer storage is often referred to as “memory” to associate it with human memory. The word memory may be misleading because the computer does not have the ability to store information in a systematic way and to retrieve this information quickly and accurately.  All computers must have at least one, and preferably more, types of memory to store information. These storage places are generally classifies as primary or secondary storage.  The most important function unit of any computer is the CPU. It contains three important sections or elements: the arithmetic-logic unit, the control unit, and the memory unit.

6.  The arithmetic-logic unit does all the calculations and logic (comparisons or decisions) required for the program active in the computer. It handles the basic operations of adding, subtracting, multiplying, and counting.  Since now we are in the computer age, there will be more and more demand for people who are knowledgeable about and capable of working with computers in all aspects of manufacturing.

7.  Primary storage: 1.Magnetic core memory 2.Solid-state memory 3.RAM random access memory  Secondary storage 1.Magnetic disks 2.Magnetic bubble memory