发布时间 : 星期六 文章专业计算机英语复习材料更新完毕开始阅读5f539810f18583d049645960
As an alternative to a computer , an interpreter convert one instruction at a time while the programsrunning . An interpreter reads the first instructions, converts it into machine language ,and then sends it to the microprocessor . After the instruction is executed, the interpreter convents the next instruction , an so on.
从一本翻译成机器语言的高级语言指令过程可通过两种方案实现特殊类型：编译器和解释。编译器将所有的指示为一个单一的批处理程序，以及由此产生的机器语言指令，称为目标代码，放在一个新文件。关于为商业软件分发CD大多是编译的程序文件，使它们包含机器语言指令，随时准备为处理器来执行。
作为一台电脑的选择，翻译转换一次一个指令，而程序的运行。解释器读取第一个指令，转换成机器语言，然后将其发送到微处理器。指令执行后，解释修道院下指令，等等。
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2. Multitasking, in computer science , is a mode of operation offered by an operating system in which a computer works
on more than one task at a time. There are server types of multitasking .Context switching is a very simple type of multitasking in which two or more applications are loaded at the same time but only the foreground application is given processing time; to activate a background task , the user must bring the window or screen containing that application to the front .In cooperative multitasking ,background tasks are given processing time during idle times in the foreground task (such as when the application waits for a keystroke),and only if the application allows it .In time-slice multitasking , each task is given the microprocessor’s attention for a fraction of a second. To maintain order , task are either assigned priority levels or processed in sequential order. Because the user’s sense of time is much slower than the processing speed of the computer , time-slice multitasking operating seem to be simultaneous.50页的最后一提译文：
在计算机科学中，多任务处理是操作系统提供的一种操作方式，它使计算机一次可执行不止一项任务。多任务处理有几种类型。上下文切换是一种非常简单的多任务处理：两个或两个以上的应用程序同时装入，但只有前台应用程序得到的处理时间；要激活后台任务，用户必须将含有该应用程序的窗口或屏幕调至前面。在合作多任务处理中，后台任务在前台任务空闲期间（例如，应用程序等待键击时）得到处理时间，但条件必须是该应用程序允许这样做。在分时段的多任务处理中，每项任务得到微处理器几分之一秒的处理。为了维持次序，任务或被指定优先等级，或被按序依次处理。由于用户对时间的感觉要比计算机的处理速度慢得多，因此分时段的多任务操作看上去似乎是同时进行的。
3.many schools and businesses have established e-mail privacy policies ,which explain the conditions under which
you can an d cannot expect your e-mail to remain private. These polices are sometimes displayed when the computer boots or a new user logs in . Count decisions , however , seem to support the notion that because an organization owns and operates an e-mail system , the e-mail message on that system are also the property of the organization. The individual who authors an e-mail message does does not own all right related to it, The company or school that supplies your e-mail account can., therefore ,legally monitor your message . You should use your e-mail account with the expectation that some of your mail will be read from time to time. Think of your e-mail as a postcard , rather than a letter , and save your controversial comments for face-to-face conversations.31的译文：
许多学校与工商企业已经制定电子邮件隐私政策，阐明在什么条件下能够或不能期待电子邮件保持私密性。这些政策有时在计算机启动或新用户登入时予以显示。然而，法庭判决似乎支持以下看法：因为一个电子邮件系统为一个
机构所拥有和运行，所以上面的电子邮件也为该机构所以。电子邮件的作者并是所以与电子邮件相关的权利都拥有。因此，給你提供电子邮件帐号的公司或学校可以合法地监控你的电子邮件。使用电子邮件帐号时，你应该想到：你的一些邮件会被人不时地阅读。你应该把电子邮件视作明信片而非信件，并将可能引起争议的言论留待面谈时再说。
4. You should also keep in mind that legal constraints shape how e-mail is used in the workspace . E-mail , like
any other written document , is protected by copyright law , So, you need to be careful not to use e-mail in any way that might violate copyright law . For example, if you receive an e-mail from a client , you cannot immediately post it to your company‘s website without that client‘s permission.23页的译文：
你还应该记住，法律约束对在工作场所所如何使用电子邮件具有决定作用。像任何其他书面文档一样，电子邮件收版权法保护。因此，你得小心，不要以可能触犯版权法的任何方式使用电子邮件。例如，如果你收到一位客户的电子邮件，在没有得到该客户允许的情况下，你不能将电子邮件马上发布到你公司的网站上。
Also, lawyers and courts treat e-mail as written communication, equivalent to a memo or letter . For example, much of the antitrust case against Microsoft in the late 1990s was built on recovered e-mail message in which Bill Gates and other executives chatted informally about aggressively competing with other companies.译文：
还有，律师和法庭把电子邮件视为书面通信，将它等同于备忘录或信函。例如，20世纪90年代末针对微软的反垄断案在很大程度上机是以恢复的电子邮件为根据的；在这些电子邮件中，比尔盖茨和其他经营主管人员非正式地聊到与其他公司展开大胆有力的竞争。
4. Legally, any e-mail you send via the employer‘s computer network belongs to the employer. So, your
employers are within their right to read your e-mail without your knowledge or permission. Also , deleted e-mails can be retrieved from the company‘s servers, and they can be used in a legal case.24的译文：
从法律上讲，你通过雇主的计算机网络发送的任何电子邮件都属于雇主。因此，你的雇主有权阅读你的电子邮件而无须你知道或得到你的允许。另外，删除的电子邮件可从公司的服务器上恢复，而且它们可用于法律案件。
5. A computer system includes a computer, peripheral device, and software. The electric , electronic ,and
mechanical devices used for processing data are referred to as hardware .In addition to the computer itself , the term ―hardware‖ refers to components called peripheral devices that expend the computer‘s input , output , and storage capabilities . Computer hardware in and of itself does not provide a particularly useful mind tool , To be useful .a computer requires a set of instructions , called software or a computer program, which tells the computer how to perform a particular task. Computers become even more effective when connected to other computers in a network so users can share information.8页的译文：
计算机系统包括计算机、外围设备和软件。用于处理数据的电动、电子与机械设备称为硬件。除了计算机本身之外，“硬件”这一术语还指被称为外围设备的组建，这些外围设备可扩大计算机的输入、输出和存储能力。计算机硬件本身在本质上并未提供一件特别有用的智能工具。计算机要想变得有用，就需要有被称为软件或计算机程序的一套指令，来告诉计算机如何执行一项特定的任务。计算机在以上情况下变得更加有效；与网络中的其他计算机相连接，以使用户能够共享信息。
6. The word ―computer‖ has been part of the English language since 1646,but if you look in a dictionary printed
before1940,you might be surprised to find a computer defined as a person who performs calculations! Prior to1940, machine designed to perform calculations were referred to as calculators and tabulators .The modern