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《计算机英语(第4版)》课后练习参考答案

Unit Four/Section B

I. Fill in the blanks with the information given in the text:

1. Information engineering emphasizes a modeling tool called entity relationship diagrams.

2. One of the disadvantages of model-driven development is the long duration of projects.

3. Unlike structured analysis and design and information engineering, object-oriented

analysis and design attempt to emerge the data and process concerns into singular constructs called objects.

4. Unlike logical models, physical models show not only what a system is or does , but also

how the system is physically and technically implemented.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. check box 复选框，选择框，校验框

2. structured design 结构化设计

3. building block 积木块，构建模块，构件

4. database schema 数据库模式

5. radio button 单选（按）钮

6. 系统建模技术system modeling technique

7. 模型驱动开发model-driven development

8. 数据流程图data flow diagram

9. 下拉式菜单drop-down (或pull-down) menu

10. 滚动条scroll bar

Unit Five: Software Process

Unit Five/Section A

I. Fill in the blanks with the information given in the text:

1. New software may be developed from scratch or through the use of existing systems and

off-the-shelf software or system components.

2. The three generic process models discussed in the text are often complementary rather than

mutually exclusive, especially for large system development.

3. The waterfall model is so named because of the cascade from one phase to another in the

software development process.

4. The fundamental development activities of the waterfall model are requirements analysis

and definition, system and software design, implementation and unit testing, integration and system testing, and operation and maintenance.

5. The two fundamental types of evolutionary development are exploratory development and

throwaway prototyping.

6. The evolutionary approach is often more effective than the waterfall approach in producing

systems that meet the immediate needs of customers, but it is difficult to establish a(n) stable system architecture using this approach.

7. CBSE is a(n) reuse-oriented approach to software development, which relies on a large

base of reusable software components and an integrating framework for these components.

8. While CBSE can reduce the amount of software to be developed and the associated cost

and risks, it cannot avoid requirements compromises which may lead to a system that does not meet the real needs of users.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. system specification 系统规格说明

2. unit testing 单位（或单元、部件）测试

3. software life cycle 软件生命周期（或生存周期）

4. system validation testing 系统验证测试

5. evolutionary development process 演化开发过程

6. linear model 线性模型

7. program unit 程序单元

8. throwaway prototype 抛弃式原型

9. text formatting 正文格式编排，文本格式化

10. system evolution 系统演变

11. 系统设计范例system design paradigm

12. 需求分析与定义requirements analysis and definition

13. 探索式编程方法exploratory programming approach

14. 系统文件编制system documentation

15. 瀑布模型waterfall model

16. 系统集成system integration

17. 商用现成软件commercial off-the-shelf (或COTS) software

18. 基于组件的软件工程component-based software engineering (CBSE)

19. 软件维护工具software maintenance tool

20. 软件复用software reuse

IV. Translate the following passage from English into Chinese:

Software processes are complex and, like all intellectual and creative processes, rely on people making decisions and judgments. Because of the need for judgment and creativity, attempts to automate software processes have met with limited success. Computer-aided software engineering (CASE) tools can support some process activities. However, there is no possibility, at least in the next few years, of more extensive automation where software takes over creative design from the engineers involved in the software process.

One reason the effectiveness of CASE tools is limited is because of the immense diversity of software processes. There is no ideal process, and many organization have developed their own approach to software development. Processes have evolved to exploit the capabilities of the people in an organization and the specific characteristics of the systems that are being developed. For some systems, a very structured development process is required while for others a flexible, agile process is likely to be more effective.

软件过程比较复杂，而且像所有其他的智能和创造性过程一样，依靠人们作出决定和判断。由于需要判断和创造性，使软件过程自动化的尝试只取得了有限的成功。计算机辅助软件工程工具可支持软件过程的某些活动。然而，至少是在未来几年内，不可能实现更广泛的软件过程自动化，使软件能够接替参与软件过程的工程师来从事创造性设计。

计算机辅助软件工程工具的有效性有限，原因之一是软件过程多种多样。不存在理想的过程，而且许多组织机构发展了自己的软件开发方法。软件过程不断演变，以利用组织机构中的人员的能力和开发中的系统的具体特点。对于一些系统来说，需要的是一个高度结构化的开发过程，而对于另外一些系统来说，一个灵活敏捷的过程很可能更为有效。

Unit Six: Database

Unit Six/Section A

I. Fill in the blanks with the information given in the text:

1. Data storage traditionally used individual, unrelated files, sometimes called flat files.

2. According to the text, a DBMS is a combination of five components: hardware, software,

data, users, and procedures.

3. As far as a DBMS is concerned, users can refer to both end users and application programs,

and end users can refer to both database administrators and normal user.

4. The three-level architecture for a DBMS discussed in the text consists of the internal,

conceptual, and external levels.

5. In the relational database models, data is organized in two-dimensional tables called

relations.

6. A distributed database can be classified either as a fragmented distributed database or as a

replicated distributed database.

7. While trying to keep the advantages of the relational model, an object-oriented database

allows applications to access structured data.

8. An important step in the design of a database involves the building of a(n)

entity-relationship model that defines the entities for which some information must be maintained, the attributes of these entities, and the relationship between these entities.

II.Translate the following terms or phrases from English into Chinese and vice versa:

1. end user 最终用户，终端用户

2. atomic operation 原子操作

3. database administrator 数据库管理员

4. relational database model 关系数据库模型

5. local data 本地数据

6. object-oriented database 面向对象数据库

7. database management system (DBMS) 数据库管理系统

8. entity-relationship model (ERM) 实体关系模型

9. distributed database 分布式数据库

10. flat file 平面文件

11. 二维表two-dimensional table

12. 数据属性data attribute

13. 数据库对象database object

14. 存储设备storage device

15. 数据类型data type

16. 数据插入与删除data insertion and deletion

17. 层次数据库模型hierarchical database model

18. 数据库体系结构database architecture

19. 关系数据库管理系统relational database management system (RDBMS)

20. 全局控制总线global control bus

IV. Translate the following passage from English into Chinese:

In a relational database, the rows of a table represent records (collections of information about separate items) and the columns represent fields (particular attributes of a record). In conducting searches, a relational database matches information from a field in one table with information in a corresponding field of another table to produce a third table that combines requested data from both tables. For example, if one table contains the fields EMPLOYEE-ID, LAST-NAME, FIRST-NAME, and HIRE-DATE, and another table contains the fields DEPT, EMPLOYEE-ID, and SALARY, a relational database can match the EMPLOYEE-ID fields in the two tables to find such information as the names of all employees earning a certain salary or the departments of all employees hired after a certain date. In other words, a relational database uses matching values in two tables to relate information in one to information in the other. Microcomputer database products typically are relational databases.

在关系数据库中，表的行表示记录（关于不同项的信息集），列表示字段（一个记录的特定属性）。在进行搜索时，关系数据库将一个表中的一个字段的信息与另一个表的一个相应字段的信息进行匹配，以生成将来自这两个表的所要求数据结合起来的另一个表。例如，如果一个表包含EMPLOYEE-ID、LAST-NAME、FIRST-NAME和HIRE-DATE字段，另一个表包含DEPT、EMPLOYEE-ID和SALARY字段，关系数据库可匹配这两个表中的EMPLOYEE-ID字段，以找到特定的信息，如所有挣到一定薪水的雇员的姓名或所有在某个日期之后受雇的雇员所属的部门。换言之，关系数据库使用

两个表中的匹配值，将一个表中的信息与另一个表中的信息联系起来。微型计算机数据库产品一般是关系数据库。

Unit Six/Section B

I. Fill in the blanks with the information given in the text:

1. The commit point is the point at which all the steps in a transaction have been recorded in

the log of the DBMS.

2. A large DBMS often contain a scheduler to coordinate time-sharing among transactions in

much the same way that a time-sharing operating system coordinates interweaving of processes.

3. The items within a database that are currently being used by some transaction are marked

with locks. There are two common types of locks: shared locks and exclusive locks.

4. With the wound-wait protocol, if an older transaction requires access to an item that is

locked by a younger transaction is forced to release all of its data items, and its activities are rolled back.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. nonvolatile storage system 非易失性存储系统

2. equipment malfunction 设备故障

3. wound-wait protocol 受伤―等待协议

4. exclusive lock 排它锁，互斥（型）锁

5. database integrity 数据库完整性

6. 共享锁shared lock

7. 数据库实现database implementation

8. 级联回滚cascading rollback

9. 数据项data item

10. 分时操作系统time-sharing operating system

Unit Seven: Computer Networks

Unit Seven/Section A

I. Fill in the blanks with the information given in the text:

1. According to the geographical area covered, a computer network is often classified as either

a LAN, a (n) MAN, or a WAN.

2. A network can also be classified as either a (n) open network or a (n) closed network

according to whether its internal operation is based on designs in the public domain or on innovations owned and controlled by a particular entity.

3. A network can also be classified according to its topology. Among the most popular

topologies are the bus topology, ring topology, and star topology.

4. A popular protocol in networks based on the ring topology is the token ring protocol

developed by IBM in the 1970s.

5. In a (n) Ethernet system, the right to transmit messages is controlled by the protocol known

as CSMA/CD.

6. The client/server model for interprocess communication defines the basic roles played by

the processes as either a client or a server.

7. The peer-to-peer model involves two processes communicating as equals and usually

executing on a (n) temporary basis.

8. Although it is often used, the term peer-to-peer network is not very appropriate.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. file server 文件服务器

2. carrier sense 载波检测，载波监听

3. protocol suite 协议组，协议集

4. peer-to-peer model 对等模型

5. bus topology network 总线拓扑网络

6. inter-machine cooperation 机器间合作，计算机间合作

7. Ethernet protocol collection 以太网协议集

8. proprietary network 专有网络

9. utility package 实用软件包，公用程序包

10. star network 星形网络

11. 局域网local area network (LAN)

12. 令牌环token ring

13. 无线网络wireless network

14. 封闭式网络closed network

15. 环形拓扑结构ring topology

16. 客户机／服务器模型client/server model

17. 网络应用程序network application

18. 进程间通信interprocess communication

19. 打印服务器print server

20. 广域网wide area network (WAN)

IV. Translate the following passage from English into Chinese:

A network, in computer science, is a group of computers and associated devices that are

connected by communications facilities. A network can involve permanent connections, such as cables, or temporary connections made through telephone or other communications links. A network can be as small as a local area network consisting of a new computers, printers, and other devices, or it can consist of many small and large computers distributed over a vast geographic area. Small or large, a computer network exists to provide computer users with the means of communicating and transferring information electronically. Some types of communication are simple user-to-user messages; others, of the type known as distributed processes, can involve several computers and the sharing of workloads or cooperative (合作的) efforts in performing a task.

在计算机科学中，网络是指由通信设备连接在一起的一组计算机及其相关设备。网络可采用电缆等永久性连接，或者采用通过电话或其他通信链路而实现的临时性连接。

网络可以小到由少数计算机、打印机以及其他设备构成的局域网，也可以由分布在广大地理区域的许多小型与大型计算机组成。计算机网络无论大小，其存在的目的均在于为计算机用户提供以电子方式进行信息通信与传送的方法。有些类型的通信是简单的用户到用户消息；有些称为分布式过程，可能涉及数台计算机，以及在执行任务中分担工作量或进行协作。

Unit Seven/Section B

I. Fill in the blanks with the information given in the text:

1. In the bus topology, a terminator should be installed at each end of the bus or main cable.

2. As compared with the star topology, the extended star topology adds sub-central devices

instead of connecting all devices to a central unit.

3. The hierarchical topology, also referred to as the tree topology, is much like the star

topology, except that it doesn’t use a (n) central node.

4. A truly redundant network can be created with the mesh topology.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. routing path 路由选择通路

2. dual-ring topology 双环形拓扑结构

3. extended star topology 扩展星形拓扑结构

4. backbone network 基干网，骨干网

5. mesh topology 网格拓扑结构

6. 同轴电缆coaxial cable

7. 逻辑拓扑结构logical topology

8. 无冲突连网环境collision-free networking environment

9. 树形拓扑结构tree topology

10. 目的地节点destination node

Unit Eight: The Internet

Unit Eight/Section A

I. Fill in the blanks with the information given in the text:

1. The Internet originated from research projects going back to the early 1960s.

2. The establishment of domains on the Internet is overseen by a nonprofit corporation called

ICANN或the Internet Corporation for Assigned Names and Numbers.

3. A registered domain can be attached to the existing Internet by means of a (n) router which

is often referred to as the gateway of the domain.

4. A user typically connects to the Internet in one of two ways: temporary/dial-up

connections and permanent/dedicated connections.

5. A (n) ISP或Internet service provider is a company that provides Internet access and

other services to customers.

6. An IP address is a 32-bit address made up of two parts: the network identifier and the host

address, identifying the domain in which a computer resides and the particular computer within the domain respectively.

7. IP address are traditionally written in dotted decimal notation.

8. For ease of memorization, each domain is also assigned a unique mnemonic address known

as a domain name.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. cell phone 蜂窝电话，移动电话，手机

2. IP address 网际协议地址，IP地址

3. autonomous system 自主系统

4. dial-up connection 拨号连接

5. network identifier 网络标识符

6. binary notation 二进制记数法

7. mnemonic name 助记名，缩写名

8. Internet-wide directory system 因特网范围的目录系统

9. name server 名称服务器

10. Internet infrastructure 因特网基础结构

11. 助记地址mnemonic address

12. 网吧cyber cafe

13. 宽带因特网访问broadband Internet access

14. 顶级域名top-level domain (TLD)

15. 因特网编址Internet addressing

16. 点分十进制记数法dotted decimal notation

17. 因特网服务提供商Internet service provider (ISP)

18. 专用因特网连接dedicated Internet connection

19. 主机地址host address

20. 硬件与软件支持hardware and software support

IV. Translate the following passage from English into Chinese:

The internet provides only the physical and logical infrastructure that connects millions of computers together. Many believe that the World Wide Web (WWW, or simply the Web) provides the killer application (制胜法宝) for this global network. The Web is considered the content of the Internet, providing all sorts of information by using a rich set of tools that manage and link text, graphics, sound, and video. Providing and viewing information on the Web is accomplished server applications and client applications.

If you’ve already explored the Web, you’ll recognize the client-side application as the Web browser. A Web browser receives, interprets, and displays pages of information from the Web. The user can navigate within pages, jump to other pages by clicking hypertext links, and point to just about any page on the Web.

因特网只是提供了将许许多多的计算机连接在一起的物理与逻辑基础结构。不少人认为，是万维网（WWW或简称the Web）为这个全球网络提供了“制胜法宝”。万维网被视为因特网的内容，它通过使用管理与链接文本、图形、声音和视频的一套丰富工具来提供各种信息。在万维网上提供和查看信息，是使用服务器应用程序和客户应用程序完成的。

如果你已经探索过万维网，你就会看出客户端应用程序就是万维网浏览器。万维网浏览器接收、解释和显示来自万维网的网页信息。用户可以在网页之内浏览，可以通过点击超文本链接跳到其他网页，也可以指向万维网上的几乎任何网页。

Unit Eight/Section B

I. Fill in the blanks with the information given in the text:

1. For an outgoing message, the four layers of software involved in Internet communication

work in the order of the application layer, the transport layer, the network layer, and the link layer; for an incoming message, it is just the opposite.

2. The transport layer converts long messages into packets compatible with the Internet

before their transmission and reassembles them at the destination.

3. The packets related to a common message may follow different paths through the Internet.

4. Only the link and network layers are involved at the intermediate stops during a packet’s

journey to its final destination.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. incoming message 来报，到来的报文

2. application layer 应用层

3. utility software 实用软件

4. sequence number （顺）序号，序列号

5. remote login capabilities 远程登录能力

6. 端口号port number

7. 软件例程software routine

8. 传输层transport layer

9. 文件传送协议FTP（File Transfer Protocol）

10. 万维网浏览器Web browser

Unit Nine: Mobile and Cloud Computing

Unit Nine/Section A

I. Fill in the blanks with the information given in the text:

1. The concept of cloud computing has evolved from cluster, grid, and utility computing.

2. A public cloud is built over the Internet and can be accessed by any user who has paid for

the service.

3. A private cloud is built within the domain of a (n) intranet owned by a single organization.

4. A (n) hybrid cloud is built with both public and private clouds.

5. Generally speaking, private clouds are easier to manage, and public clouds are easier to

access.

6. The rapid progress in multi-core CPUs, memory chip, and disk arrays has made it possible

to built faster data centers with huge amounts of storage space.

7. One of the design objectives for cloud computing is shifting computing from desktops to

data centers

8. The Internet cloud is envisioned as a massive cluster of servers, which can be physical

machines or VMs.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. server farm 大型机服务器

2. access protocol 存取协议，访问协议

3. storage area network 存储区域网（络）

4. high-throughput computing 高吞吐（量）计算

5. server cluster 服务器集群

6. public cloud 公共云

7. grid computing 网格计算

8. security-aware cloud architecture 具有安全意识的云体系结构

9. social networking 社交网络

10. utility computing 效用计算

11. 云计算提供商cloud computing provider

12. 存储芯片memory chip

13. 基于内部网的私有云intranet-based private cloud

14. 网络带宽network bandwidth

15. 混合云hybrid cloud

16. 磁盘阵列disk array

17. 软件即服务Software as a Service (SaaS)

18. 集群计算cluster computing

19. 虚拟化计算机资源virtualized computer resources

20. 多核处理器multi-core processor

IV. Translate the following passage from English into Chinese:

Cloud computing applies a virtualized platform with elastic resources on demand by provisioning hardware, software, and data sets dynamically. The idea is to move desktop computing to a service-oriented platform using server cluster and huge databases at data centers. Cloud computing leverages its low cost and simplicity to benefit both users and providers. Machines virtualization has enabled such cost-effectiveness. Cloud computing intends to satisfy many user applications simultaneously. The cloud ecosystem(生态系统) must be designed to be secure, trustworthy, and dependable. Some computer users think of the cloud as a centralized resource pool. Others consider the cloud to be a servers used.

Traditionally, a distributed computing system tends to be owned and operated by an autonomous administrative domain (e. g., a research laboratory or company) for on-premises (机构内部的) computing needs. However, these traditional systems have encountered several performance bottlenecks (瓶颈): constant system maintenance, poor utilization, and increasing costs associated with hardware/software upgrades (升级). Cloud computing as an on-demand computing paradigm resolves or relieves us from these problems.

云计算动态供应硬件、软件和数据集，以此方式按需应用一个拥有弹性资源的虚拟化平台。其目的是通过在数据中心使用服务器集群和巨型数据库而将桌面计算转移到一个面向服务的平台。云计算充分利用其低成本与简单的特性既惠及用户也惠及提供商。

机器虚拟化使这样的成本效益成为可能。云计算意在同时满足许多用户应用程序的需要。云生态系统必须设计得具有安全性、可信性和可靠性。有些计算机用户将云视为一个集中式资源池，而另外一些计算机用户则认为云是一个在所用的各个服务器上实行分布式计算的服务器集群。

传统上，一个分布式计算系统往往由一个自主管理域（如一个研究实验室或公司）为内部计算需要而拥有和使用。然而，这些传统系统遭遇数个性能瓶颈：系统维护需要不断进行；利用率差；与硬件／软件升级有关的费用日益增长。作为一种按需计算范式，云计算可解决这些问题或可使我们摆脱这些问题。

Unit Nine/Section B

I. Fill in the blanks with the information given in the text:

1. Supportive technologies for the IoT are divided into two categories: enabling and

synergistic technologies.

2. Contemporary devices that lend support to ubiquitous computing include smartphones,

tablet computers, sensor networks, RFID tags, smart cards, and GPS devices.

3. The architecture of an IoT consists of sensing devices connected to various applications via

mobile networks, the Internet, and processing clouds.

4. A typical wireless sensor network consists of spatially distributed autonomous sensors to

cooperatively monitor physical or environmental conditions.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. computer vision 计算机视觉

2. ubiquitous computing 普适计算

3. command line 命令行

4. data logging system 数据记录（或登录）系统

5. augmented reality 增强现实

6. 移动网络mobile network

7. 平板电脑tablet computer

8. 物联网Internet of Things

9. 智能电网smart power grid

10. 传感器融合sensor fusion

Unit Ten: Computer Security

Unit Ten/Section A

I. Fill in the blanks with the information given in the text:

1. The CIA triad used to define computer security objectives consists of confidentiality,

integrity, and availability.

2. In computer security, integrity covers the two related concepts of data integrity and system

integrity.

3. In addition to the CIA triad, two of the most commonly mentioned concepts concerning

security objectives are authenticity and accountability.

4. Security concerns with respect to data encompass availability, secrecy, and integrity

5. Passive network security attacks attempt to learn or make use of information from the

system without affecting system resources, whereas active attacks attempt to alter system resources or affect their operation.

6. A key threat to software is an attack on availability

7. In developing a security policy, a security manager must balance ease of use against

security against cost of failure and recovery.

8. In the context of computer security, assurance is the degree of confidence one has that the

security measures work as intended.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. backup system 备份系统

2. encryption key （加密）密钥

3. data confidentiality 数据机密性

4. system vulnerability 系统脆弱性，系统脆弱之处

5. unauthorized access 未经授权的访问，越权存取

6. intrusion detection system 入侵检测系统

7. after-action recovery 事后恢复

8. software piracy 软件侵权

9. authorized user 特许用户

10. data unit 数据单元，数据单位

11. 软件版本software version

12. 数据完整性data integrity

13. 系统崩溃system crash

14. 病毒检查软件virus-checking software

15. 综合安全策略comprehensive security strategy

16. 软件配置管理software configuration management

17. 故障隔离fault isolation

18. 统计数据库statistical database

19. 保密的加密算法secure encryption algorithm

20. 数据流data stream

IV. Translate the following passage from English into Chinese:

Intruder (入侵者) attacks range from the benign (良性的，温和的) to the serious. At the begin end of the scale, there are many people who simply wish to explore internets and see what is out there. At the serious end are individuals who are attempting to read privileged data, perform unauthorized modifications to data, or disrupt the system.

The objective of the intruder is to gain access to a system or to increase the range of privileges accessible on a system. Most initial attacks use system or software vulnerabilities that allow a user to execute code that opens a back door into the system. Intruders can get access to a system by exploiting attacks such as buffer overflows (缓存溢出) on a program that runs with certain privileges.

Alternatively, the intruder attempts to acquire information that should have been protected. In some cases, this information is in the form of a user password. With knowledge of some other users’password, an intruder can log in to a system and exercise all the privileges accorded to the legitimate user.

入侵者攻击从温和的到严重的形形色色。在这一系列攻击的温和端，有许多人只是希望探查互联网，看看那里有什么。在严重端的是试图阅读特许数据、对数据进行未经授权的修改或扰乱系统的个人。

入侵者的目标是获得进入一个系统的机会，或者增加在一个系统中可以使用的特权范围。初始攻击大多利用系统或软件的脆弱之处，这些脆弱之处允许用户执行相应的代码，打开进入系统的后门。入侵者可对具有某些运行特权的程序实施像缓存溢出这样的攻击，利用此类攻击获得进入一个系统的机会。

另外，入侵者也试图获取应予保护的信息。在有些情况下，这种信息是以用户口令的形式存在的。知道了某个其他用户的口令之后，入侵者就可以登录系统并行使赋予合法用户的所有特权。

Unit Ten/Section B

I. Fill in the blanks with the information given in the text:

1. Most commercial antivirus software uses both the virus dictionary approach and the

suspicious behavior approach with emphasis on the virus dictionary approach.

2. An emerging technique to deal with malware in general is whitelisting which prevents

execution of all computer code except that which has been previously identified as trustworthy by the system administrator.

3. Instead of attempting to identify known viruses, the suspicious behavior approach

provides protection against brand-new viruses that do not yet exist in any virus dictionaries.

4. Usually one should have only one type of memory-resident antivirus software installed on

a single computer.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. phishing attack 网络钓鱼攻击

2. graphics card 显（示）卡

3. heuristic analysis 试探性分析

4. infected file 被感染文件

5. virus dictionary 病毒字典

6. 数据捕获data capture

7. 恶意软件malicious software

8. 病毒特征代码virus signature

9. 防病毒软件antivirus software

10. 内存驻留程序memory-resident program

Unit Eleven: Cyberculture

Unit Eleven/Section B

I. Fill in the blanks with the information given in the text:

1. When professional website designers determine the number of levels in a website, a

guideline usually followed is that there should be a maximum of three links for the most important information.

2. A website has a few different kinds of webpages: the homepage, node pages, basic pages,

navigation pages, and the optional splash page.

3. According to the text, the five principles of design for the interface of a website are balance,

alignment, grouping, consistency, and contrast.

4. Before uploading your website, you should do some usability testing to ensure quality.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. web-authoring software 网络写作软件

2. template generator 模版生成程序

3. navigation page 导航页面

4. corporate logo 公司标识

5. splash page 醒目页面，过渡页

6. 导航条navigation bar

7. 节点页面node page

8. 网站地图site map

9. 可用性测试usability testing

10. 图形交换格式gif（Graphics Interchange Format）

Unit Twelve: Electronic Commerce

Unit Twelve/Section B

I. Fill in the blanks with the information given in the text:

1. All electronic commerce sites must at least provide a catalog display, shopping cart

capabilities, and transaction processing.

2. Small commerce sites can use a(n) static catalog while larger commerce sites are more

likely to use a(n) dynamic catalog.

3. A shopping cart is sometimes called a shopping bag or shopping basket.

4. At checkout, the online shopper’s Web browser software and the seller’s Web server

software both switch into a secure state of communication.

II. Translate the following terms or phrases from English into Chinese and vice versa:

1. software suite 软件套件

2. text box 文本框

3. virtual checkout counter 虚拟付款台

4. static catalog 静态目录

5. browser session 浏览器会话期

6. 动态目录dynamic catalog

7. 购物车软件shopping cart software

8. 供应链supply chain

9. 企业资源计划软件enterprise resource planning (ERP) software

10. 税率tax rate

《最新英美概况》练习参考答案(美国部分)

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课后练习参考答案

课后练习参考答案 Unit 3 Topic 1 Section A ※课后练习I. 1-5 BBDBD 6. D 7. D 8. D II. 1. throughout 2. characters 3. cartoon 4. are ready for 5. are pleased with/at 6. garage 7. film-maker 8. foreigners III. 1. Are you ready for the trip? 2. Thank you. 3. am very pleased with 4. Don't worry. 5. Try your best and work much harder Topic 1 Section B ※课后练习I. 1-5 DACBC II. 1. interpreters 2. dug 3. twins 4. tonight 5. impossible III. 1-5 BDCAE Topic 1 Section C ※课后练习I.1-5 AAACC II. 1. European 2. trader/businessman 3. root 4. conferences 5. tourists III. 1-5 BBCAB Topic 1 Section D ※课后练习I. 1-5 CBBCA II. 1. try 2. afraid 3. English 4. way 5. what 6. easily 7. worry 8. something 9. in 10. look III.1. The tree is planted by them. 2. The apple is divided into halves. 3. Disneyland is enjoyed by millions of children. Unit 3 Topic 2 Section A ※课后练习I. 1-6 CBCBCB II. 1. stranger 2. Whenever 3. ask for a ride 4. worried about 5. see her off III. 1. is going 2. is moving 3. is leaving 4. are coming 5. are flying Ⅳ. 1. Get on the train 2. What's up?/ What's the matter? 3. Could you please give me a ride? 4. What time is the next flight? 5. I'm coming. Topic 2 Section B ※课后练习I. 1-6 BCDBD II. 1. victory 2. praise 3. silent 4. secret 5. research III. 1-5 ACBBC 6-10 ABBCA Topic 2 Section C ※课后练习I. 1-5. BCCBA II. 1. pride 2. positive 3. courage 4. attention 5. negative III. 1-5 CBCAA Topic 2 Section D ※课后练习I.1-5 CAACA II. 1. Pronunciation 2. totally 3. spelling III. 1. always 2. winters 3.summers 4. sets 5. changed 6. animals 7. as 8. more 9. used 10. weather Ⅳ. 1. Peter is flying to Paris tomorrow. 2. Body language is the second language. 3. British English is different from American English. Unit 3 Topic 3 Section A ※课后练习I. 1-5 BAAAD 6. A 7. D II. 1. dare 2. copies 3. sleepy 4. accents 5. notebook 6. tapes 7. retell 8. composition 9. oral III. 1. How nice to see you back! 2. afraid of 3. Me, too. 4. Who is good at English at the class? 5. I don't know what to do next. Topic 3 Section B ※课后练习I. 1-5 BABBA II. 1. ability 2. aloud 3. objects 4. toothpaste III. 1-5 BCBAC 6-10 CABCA Topic 3 Section C ※课后练习I. 1-5 BDCDB II. 1. translate 2. exactly 3. achieve 4. discussion III. 1-5 DCABA

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工程造价管理试题及答案 Standardization of sany group #QS8QHH-HHGX8Q8-GNHHJ8-HHMHGN#

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有机化学课后习题参考答案完整版

目录lin 湛

第一章绪论扼要归纳典型的以离子键形成的化合物与以共价键形成的化合物的物理性质。答案： NaCl与KBr各1mol溶于水中所得的溶液与NaBr及KCl各1mol溶于水中所得溶液是否相同？如将CH4及CCl4各1mol混在一起，与CHCl3及CH3Cl各1mol的混合物是否相同？为什么？答案： NaCl与KBr各1mol与NaBr及KCl各1mol溶于水中所得溶液相同。因为两者溶液中均为Na+,K+,Br－, Cl－离子各1mol。由于CH4与CCl4及CHCl3与CH3Cl在水中是以分子状态存在，所以是两组不同的混合物。碳原子核外及氢原子核外各有几个电子？它们是怎样分布的？画出它们的轨道形状。当四个氢原子与一个碳原子结合成甲烷（CH4）时，碳原子核外有几个电子是用来与氢成键的？画出它们的轨道形状及甲烷分子的形状。答案：写出下列化合物的Lewis电子式。答案：下列各化合物哪个有偶极矩？画出其方向。答案：根据S与O的电负性差别，H2O与H2S相比，哪个有较强的偶极-偶极作用力或氢键？答案：电负性O>S,H2O与H2S相比，H2O有较强的偶极作用及氢键。下列分子中那些可以形成氢键？ b. CH3CH3 c. SiH4 d. CH3NH2 e. CH3CH2OH f. CH3OCH3 答案： d. CH3NH2 e. CH3CH2OH 醋酸分子式为CH3COOH，它是否能溶于水？为什么？答案：能溶于水，因为含有C=O和OH两种极性基团，根据相似相容原理，可以溶于极性水。第二章饱和烃卷心菜叶表面的蜡质中含有29个碳的直链烷烃，写出其分子式。答案：C29H60 用系统命名法（如果可能的话，同时用普通命名法）命名下列化合物，并指出(c)和(d)中各碳原子的级数。答案： a. 2,4,4－三甲基－５－正丁基壬烷５－butyl－2,4,4－trimethylnonane b. 正己烷 hexane ,3－二乙基戊烷 3,3－diethylpentane －甲基－５－异丙基辛烷５－isopropyl－3－methyloctane e.２－甲基丙烷（异丁烷）２－methylpropane(iso-butane) ,2－二甲基丙烷（新戊烷） 2,2－dimethylpropane(neopentane)

(完整word版)大学英语一期末考试题以及答案

精心整理大学英语（一）行政班级分级班级姓名学号 C. A measuring system. D. A control system. 2. A. Car prices. B. Car services.

C. The company’s business. D. The company’s culture. 3. A. It’s easy to do. B. It’s challenging. dialogue, there are some recorded questions. Both the conversations and questions will be spoken two times. Conversation 1

6. A. Breakfast. B. Dinner. C. A 5 dollar gift card. D. Bus service to the airport. 10. A. Make an appointment with her. B. Talk with her about a new order.

C. Send her an email about the shipment. D. Call her back when receiving the shipment. Directions: This part is to test your ability to construct grammatically correct sentences. It consists of 2 sections.

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