信息技术英语u.pps

2019/6/18,P.1,Unit 17,The Internet,Chapter Four,& Part4 Extensive Reading, Part 1 Notes to Text, Part5 Notes to Passage,& Part 2 Word Study, Part3 Practice on Text, Part6 Practice on Passage,2019/6/18,P.2, Part 1 Notes to Text,1) This network of networks is used for an extraordinary range of purposes - long distance collaborations, retrieving free software and documents, accessing library catalogs, logging in to supercomputers. 该网络的应用范围也特别广 远距离合作、检索免费软件和文档、查阅图书馆目录、登录到超级计算机上。 注释：破折号后面的long distance collaborations, retrieving free software and documents, accessing library catalogs, logging in to supercomputers都是名词性短语，用作同位语，说明前面所提到的名词purposes的具体内容。 2) In the Internet Passport, the Internet will be defined as the network of networks which follow a set of rules known as the “Internet Protocol (IP) suite“. 人们将因特网在它的证书中定义为网络群中的网络，该网络群遵循的是一套所谓的互联网协议集规则。 注释：注意定语从句which follow a set of rules known as the “Internet Protocol (IP) suite“中的关系代词which指代的先行词是networks而非network，所以用的是复数谓语动词形式；过去分词短语known as修饰rules。,The Internet,2019/6/18,P.3,3) It means that any computer which is connected to the Internet can communicate with any other Internet computer thanks to the rules of IP, and that a message sent from one Internet computer to another will get to the intended destination. 这就意味着，有了IP协议的作用，任意一台连接到因特网上的计算机就可以与因特网上任何其它计算机进行通信联系；也意味着可以将信息从因特网上的一台计算机传送往另一台计算机上的信息，从而实现将信息送达指定地点之目的。 注释：短语thanks to the rules of IP 作原因状语；谓语动词 means后面带了两个宾语从句：一是that any computer which is connected to the Internet can communicate with any other Internet computer, 其中which is connected to the Internet为定语从句，修饰该从句的主语any computer；另一个是that a message sent from one Internet computer to another will get to the intended destination，其中sent from one Internet computer to another 是过去分词短语作定语，修饰该从句的主语a message。,2019/6/18,P.4,4）The Internet contains the electronic equivalents of conference rooms and cafes, libraries and bookstores, post offices and telephones, radio and television stations, newspaper and magazines, and a growing variety of services that have no counterparts in “the real world“. 如今因特网拥有了各种各样等同于电子的业务，如电子会议室和咖啡屋、电子图书馆和书店、邮政局和电话局、无线电台和电视台、报社和杂志社的电子业务，以及“现实世界”中尚未出现的各种业务。 注释：名词短语the electronic equivalents和后面of结构属于同位关系。即of后面所列举的那一连串的业务都是以电子的形式开展的。通称为“电子等同业务”。 5) These services have created a truly global village where people communicate with each other not because they happen to live in the same place, but because they share the same interests. 这些服务已经形成了一个真正的地球村，人们在那里相互交流，但并非是因为碰巧住在一起，而是因为他们兴趣相投的缘故。 注释：主语These services 指上文中提到的因特网所能提供的那些服务；注意 where引导的定语从句中的连词短语not because but because 的意思是“不是因为而是因为”,是典型的原因状语。,End,2019/6/18,P.5,End,& Part 2 Word Study,2019/6/18,P.6,Task 1: Listening training Dictation of some key words Directions: You will hear some key words twice, most of which are taken from the Word Study. Then finish the Crossword Puzzle. (See you book p. ),2. Dictation of some key expressions Directions: You will hear some key expressions twice, most of which are taken from this text. Then you are asked to complete the missing words., Part3 Practice on Text,applications,incredibly,distinctive,intended,equivalents,essence,2019/6/18,P.7,Read and Reply,Directions:Students are required to read aloud the whole text after the teacher. Then give short answers to the following questions:,Task 2: Read, Write and Translate,An internet is a computer network which allows computers with distinctive software and hardware to communicate, or “internetwork“. While the Internet is specific kind of internet which is defined as the network of networks that follow a set of rules known as the “Internet Protocol (IP) suite“.,It is used for an extraordinary range of purposes, such as, long distance collaborations, retrieving free software and documents, accessing library catalogs, logging in to supercomputers,We can use the Internet to access various of kinds of resources and communicate with other people throughout the world.,c) What can we use the Internet for?,a) What is an internet and what is the Internet?,b) What is the network of networks used for?,2019/6/18,P.8,( )1) The list of current Internet activities and services is large and the range of possible future applications is limited . ( )2) Because it is in direct communication with satellites far above us, it could even be said that the Internet is already bigger than the Earth. ( )3) Many kinds of computers can be connected to an internet, but each computer can not serve a specialized role, not allowing an internet to offer a wide variety of services to its users. ( )4) You can dial from your phone to any other phone on the system no matter what kind of telephone you have; you dont need to know the phone number of the person you want to reach. ( )5) We can get various kinds of resources and communicate with others so long as the computer is connected with the Internet, no matter how cheap your computer is.,Read and Judge,End,F,T,F,F,T,2019/6/18,P.9,Directions:Read the following short passage. Complete it by filling in the missing words.,Read and Complete,End,D,C,J,F,H,A,E,B,G,I,2019/6/18,P.10,1)众所周知，因特网的功能和业务范围非常广泛，其将来的应用超出了我们的想象。(imagination) 2)据说因特网已经比地球还大了。没有人能真正全部了解它。（it is said that） 3)幸亏有了因特网，无论身在何处，我们可以随时和人们交流。(thanks to) 4)只要你连接因特网，你就可以访问遍及全世界的计算机上的资源。(access) 5)人们可以相互交流，不是因为我们住在一起，而是因为有共同的兴趣。（not becausebut because）,Read and Translate,Directions:Put the following sentences into English, using the words or phrases given.,End,As we all know, the activities and services of the Internet are so large that the future applications are beyond our imagination,It is said that the internet is already bigger that the earth and that not a single person can really understand it.,Thanks to the Internet, we can communicate with people, no matter where we are.,So long as your computer is connected to the Internet, you can access the resources of thousands of computers throughout the world.,People can communicate with each other, not because they happen to live in the same place, but because they share the same interests.,2019/6/18,P.11,Local Area Network,Local area data networks，normally referred to simply as local area networks or LANs，are used to interconnect distributed communities of computer-based DTEs located within a single building or localized(使局部化 ) group of buildingsFor example，a LAN may be used to interconnect workstations distributed around offices within a single building or a group of buildings such as a university campusAlternatively，it may be used to interconnect computer-based equipment distributed around a factory or hospital complex(综合性建筑)Since all the equipment is located within a single establishment(公司, 企业)，however，LANs are normally installed and maintained by the organizationHence they are also referred to as private data networks,& Part4 Extensive Reading,2019/6/18,P.12,The main difference between a communication path established using a LAN and a connection made through a public data network is that a LAN normally offers much higher data transmission rates because of the relatively short physical separations(间隔，距离)involvedIn the context of the ISO Reference Model for OSI，however，this difference manifests itself only at the lower network dependent layersIn many instances the higher protocol layers in the reference model are the same for both types of network Most wide area networks，such as the PSTN(公共电话交换网)，use a mesh(网状)（sometimes referred to as a network）topology (拓扑结构)With LANs，however，the limited physical separation of the subscriber DTEs allows simpler topologies to be usedThe four topologies in common use are star，bus，ring and hub(集线器),2019/6/18,P.13,The most widespread topology for LANs designed to function (起作用)as data communication subnetworks(子网络)for the interconnection of local computer-based equipment is the hub topology, which is a variation(变体, 变种)of the bus and ringSometimes it is called hub/tree topology Two techniques have been adopted for use of the medium access control in the LANsThey are carrier-sense-multiple-access with collision(冲突)detection（CSMACD），for bus network topologies，and control token(控制令牌)，for use with either bus or ring networks,End,2019/6/18,P.14, Part5 Notes to Passage,1)Local area data networks，normally referred to simply as local area networks or LANs，are used to interconnect distributed communities of computer-based DTEs located within a single building or localized group of buildings. 局域数据网一般简称为局域网，通常是用来将分散在一幢楼宇内或建筑楼群范围内的基于计算机数据终端设备互连起来。 注释：过去分词短语normally referred to simply as local area networks or LANs 为插入语，进一步说明、解释前面所提到的Local area data networks。注意该短语是动词短语refer sth. as sth.的被动结构形式；而located within a single building和localized group of buildings 均为过去分词短语作定语，修饰distributed communities；DTEs= Data Terminal Equipment(数据终端设备)。,2019/6/18,P.15,2)The main difference between a communication path established using a LAN and a connection made through a public data network is that a LAN normally offers much higher data transmission rates because of the relatively short physical separations involved用局域网方式建立的通信线路和通过公用数据网连接的线路两者的主要区别在于：局域网传输数据的速度通常要高得多，这是因为局域网连接的物理设备之间的距离相对来说较短。 注释：该句的主语是The main difference，所以谓语动词用的是is;介词短语between a communication path 是定语修饰主语；过去分词短语established using a LAN和made through a public data network，分别修饰a communication path和a connection；由that 引导的从句是表语。 注意名词短语the relatively short physical separations involved的字面意思是“相对较短的相关物理间距”，这里其实指的就是“局域网连接的物理设备之间的距离相对较短”。,2019/6/18,P.16,End,3)The most widespread topology for LANs designed to function as data communication subnetworks for the interconnection of local computer-based equipment is the hub topology, which is a variation of the bus and ring. 应用最广的局域网拓扑结构，在本地计算机设备互连中起着数据通信子网络作用，这种结构是集线器拓扑结构。它是总线和环形拓扑结构的变体。 注释：该句的结构看似复杂，但其实简单。我们可以将其简化为：The most widespread topology for LANs is the h