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關鍵詞：英語論文的引述學者的論述引述格式注明引文作者注明卷號
摘要：正確引用作品原文或專家、學者的論述是寫好英語論文的重要環節;既要注意引述與論文的有機統一,即其邏輯性,又要注意引述格式 (即英語論文參考文獻)的規范性)。
引述別人的觀點,可以直接引用,也可以間接引用。無論采用何種方式,論文作者必須注明所引文字的作者和出處。目前美國學術界通行的做法是在引文后以圓括弧形式注明引文作者及出處?，F針對文中引述的不同情況,將部分規范格式分述如下。
1.若引文不足三行,則可將引文有機地融合在論文中。如:
The divorce of Arnold's personal desire from his inheritance results in “the familiar picture of Victorian man alone in an alien universe”(Roper9).
這里,圓括弧中的Roper為引文作者的姓(不必注出全名);阿拉伯數字為引文出處的頁碼(不要寫成p.9);作者姓與頁碼之間需空一格,但不需任何標點符號;句號應置于第二個圓括弧后。
2.被引述的文字如果超過三行,則應將引文與論文文字分開,如下例所示:
Whitman has proved himself an eminent democratic representative and precursor, and his “Democratic Vistas”
is an admirable and characteristic
diatribe. And if one is sorry that in it
Whitman is unable to conceive the
extreme crises of society, one is certain
that no society would be tolerable whoses
citizens could not find refreshment in its
buoyant democratic idealism.(Chase 165)
這里的格式有兩點要加以注意。一是引文各行距英語論文的左邊第一個字母十個空格,即應從第十一格打起;二是引文不需加引號,末尾的句號應標在最后一個詞后。
3.如需在引文中插注,對某些詞語加以解釋,則要使用方括號(不可用圓括弧)。如:
Dr.Beaman points out that“he [Charles Darw in] has been an important factor in the debate between evolutionary theory and biblical creationism”(9).
值得注意的是,本例中引文作者的姓已出現在引導句中,故圓括弧中只需注明引文出處的頁碼即可。
4.如果擬引用的文字中有與論文無關的詞語需要刪除,則需用省略號。如果省略號出現在引文中則用三個點,如出現在引文末,則用四個點,最后一點表示句號,置于第二個圓括弧后(一般說來,應避免在引文開頭使用省略號);點與字母之間,或點與點之間都需空一格。如:
Mary Shelley hated tyranny and“looked upon the poor as pathetic victims of the social system and upon the rich and highborn...with undisguised scorn and contempt...(Nitchie 43).
5.若引文出自一部多卷書,除注明作者姓和頁碼外,還需注明卷號。如:
Professor Chen Jia's A History of English Literature aimed to give Chinese readers“a historical survey of English literature from its earliest beginnings down to the 20thcentury”(Chen,1:i).
圓括弧里的1為卷號,小寫羅馬數字i為頁碼,說明引文出自第1卷序言(引言、序言、導言等多使用小寫的羅馬數字標明頁碼)。此外,書名 A History of English Literature 下劃了線;規范的格式是:書名,包括以成書形式出版的作品名(如《失樂園》)均需劃線,或用斜體字;其他作品,如詩歌、散文、短篇小說等的標題則以雙引號標出,如“To Autumn”及前面出現的“Democratic Vistas”等。
6.如果英語論文中引用了同一作者的兩篇或兩篇以上的作品,除注明引文作者及頁碼外,還要注明作品名。如:
Bacon condemned Platoas“an obstacle to science”(Farrington, Philosophy 35).
Farrington points out that Aristotle's father Nicomachus, a physician, probably trained his son in medicine(Aristotle 15).
這兩個例子分別引用了Farrington的兩部著作,故在各自的圓括弧中分別注出所引用的書名,以免混淆。兩部作品名均為縮寫形式(如書名太長,在圓括弧中加以注明時均需使用縮寫形式),其全名分別為 Founder of Scientific Philosophy 及 The Philosophy of Francis Baconand Aristotle。
7.評析詩歌常需引用原詩句,其引用格式如下例所示。
現如今，大家都知道論文撰寫論文內容的教程都比較枯燥，針對性不強，一般不能滿足學院英語論文課程的要求，需要教師根據學生的專業特點，依據寫作教學規律，自行編寫教材。下面是學術參考網小編為朋友們搜集整理的英語論文致謝信，歡迎閱讀！
Acknowledgements
MydeepestgratitudegoesfirstandforemosttoProfessoraaa，mysupervisor，forherconstantencouragementandguidance.Shehaswalkedmethroughallthestagesofthewritingofthisthesis.Withoutherconsistentandilluminatinginstruction，thisthesiscouldnothavereacheditspresentform.
Second，IwouldliketoexpressmyheartfeltgratitudetoProfessoraaa，wholedmeintotheworldoftranslation.IamalsogreatlyindebtedtotheprofessorsandteachersattheDepartmentofEnglish：Professordddd，Professorssss，whohaveinstructedandhelpedmealotinthepasttwoyears.
Lastmythankswouldgotomybelovedfamilyfortheirlovingconsiderationsandgreatconfidenceinmeallthroughtheseyears.Ialsoowemysinceregratitudetomyfriendsandmyfellowclassmateswhogavemetheirhelpandtimeinlisteningtomeandhelpingmeworkoutmyproblemsduringthedifficultcourseofthethesis
Fan Zhang
University of Limerick
MEng. Computer and Communication Systems
ID: 0526401
Abstract: I am a video game fan, but not an addict. Since this topic attracted me a lot, I decided to choose this one as my topic for the third assignment of Processor Architecture Module. I started to play video games since I was five. While I was playing games, I found the game console itself just like a mystery, how could they react our actions to the controller then reflects so amazing pictures on TV? Although I have read a lot about it in game magazines, I admit that I didn’t try to find the answer until I found this topic. This is a great chance for me to answer the question myself. At the same time, I want to present you this paper, which should be fun.
This paper concerns the differences of architecture between PC and PlayStation 2. Since the purposes of PC and PlayStation 2 are different (or maybe I should say the purposes of PC include that of PlayStation 2), the different objectives decide the different design orientation. I think PlayStation 2 is a good game console for the comparison. First, a lot of documentations about PlayStation 2’s Emotion Engine can be found in the Internet. Second, as far as I know, PlayStation 2’s design has straightforward purposes: 3D games and multimedia, which makes the game console is seemed to be born for these two reasons. Contrasts to PlayStation, current PCs do very well on these two aspects, but the cost is the unstoppable upgrade of hardware. PlayStation 2 is a product born 5 years ago. Today tens of millions of people are still enjoy PlayStation games at home. 5-year-old PCs have been washed out already.
Keywords: PC, processor, video card, system controller, bus, Emotion Engine, Vector Unit, Graphics Synthesize.
1. INTRODUCTION
1.1 The evolution of game performance
The computer technology has achieved rapid evolution this year. From Figure 1.1 to Figure 1.5 you can see, in almost twenty years, how great changes of game performance are, both PC and game consoles.
Figure 1.1: Final Fantasy I (FC) 1987 by SQUARE
Figure 1.2: Final Fantasy XII (PlayStation 2) 2006 by SQUARE ENIX
Figure 1.3: Prince of Persia (PC) 1989 by Broderbund
Figure 1.4 Prince of Persia: The Two Thrones (PC) 2006 by Ubisoft
The screenshots above are the evidences of technique developments. In these twenty years, computers are almost 10 times faster than in the 1980’s. The cost of buying a computer is decreasing simultaneously. However, the development orientations of both PC and game consoles didn’t change much during these 20 years. Here I want to say game consoles and PC are different, although they both can be classified to ‘computer’ class, although PC includes all game consoles’ functions (but the software are not compatible each other). The differences include many areas, the architecture, the media, the software producing and selling model, and the customers.
1.2 Why they are different?
I would rather to say it is because of the distinct purposes. Of course PC can play games, can do anything that game consoles do, and in the present, PlayStation 2, the most famous game console in the world, can connect to Internet, can print paper, even can run complete Linux operating system, but PC is general purpose, this means PC should care too much things, and be good at almost everything. For instance, PC should be good at text processing, games, printing, Internet connection, a huge amount of protocols are settled for it; PC also need to compatible with all components and software that are designed and implemented by current standards. But game consoles are different. They need only care about games, which mean most designs are flexible. At the same time, the standards which PC has to obey do not affect it at all. No extra cost, no burden, only focus on games.
Figure 1.5: Sony’s PlayStation 2
1.3 Multimedia
From later 20th century, multimedia has become one of the main purposes of PC. Corresponding new technology for enhancing the capability of multimedia processing on PC has been developed as well. However, the reality of transmission speed bottleneck hasn’t been changed much. Keith Diefendorff and Pradeep K. Dubey published an article named “How Multimedia workloads will change Processor Design” in 1996. They argued the dynamic media processing would be a big challenge for current processor architecture. They also thought it will force the fundamental changes in processor design.
Before Pentium 4, the processors shared the same character: their data cache memory was big, but instruction cache memory was relatively small. It was quite useful for most usage, for instance, word editor, e-business, stock information processing, and so on. However, Diefendorff did not think it is useful, or efficient enough for multimedia processing, for multimedia data come and forth constantly, no need to settle a huge bulk of storage space for holding the information that rarely has chance of reuse. Contrarily, multimedia processing requires more calculation than others. So, for multimedia calculation, the instruction cache memory should become larger, both caches require faster transmission speed as well. We shall see this prediction has realized much in both Pentium 4 and PlayStation 2.
1.4 The purpose and the brief layout of the article
This paper is mainly talk about the architectural differences between PC and PlayStation 2, which is the most famous game console in the world. The article will discuss several aspects, the whole architecture, the CPU, the motherboard, and the graphics. In the following section, the whole architectures are compared. Two processors, Intel’s Pentium 4 and PlayStation 2’s Emotion Engine are discussed and compared in the third section. The fourth section is about the bus and caching comparison. The fifth section mainly talks about PC and PlayStation 2’s graphic devices, Video card and Graphics Synthesizer. The conclusion will be made in the last section.
2. WHOLE ARCHITECTURE COMPARISON
2.1 PC architecture
The basis of PC could root back to 1940’s. John von Neumann (1903-57), who constructed a very basis structure of computer, stayed his name in the history forever. The architecture of modern PC is still based mainly on his architecture. Let’s see a diagram of PC architecture as our basis of illustrating how PC works for game performance in the future.
Figure 2.1: PC architecture--------------------------------->
Different regions in the diagram have different clock speed. We can see the system controller is the heart of whole PC system. It carries data between processor and other components in PC over bridge. The bridge is used to connect interfaces and buses. Two kinds of bridges exist in PC, North Bridge (the system controller) and south bridge (the bus bridge). The system controller provides an interface between the processor and external devices, both memory and I/O. The system controller works with the processor to perform bus cycles.
From the diagram we can see, the system controller makes the whole diagram to be complicated. This is because the system controller has to adjust the bus cycles between the processor and the external device that it wants to access. Briefly, the PC’s working procedure can be described as follow:
PC executes commandsèaccess data with the help of system controllerèreturns the execution resultèexecute commandsè…
System controller also possesses the function of controlling DMA (Direct Memory Access), which is the ability to transfer data between memory and I/O without processor intervention.
2.2 PlayStation 2 Overview
Let’s first see the architecture of PlayStation 2.
Figure 2.2: the architecture of PlayStation 2---------------->
PlayStation 2 is composed of a graphics synthesizer, the Emotion Engine, the I/O Processor (IOP), and a Sound Processor Unit (SPU). The IOP controls peripheral devices such as controller and disk drive and detect controller input, which is sent to the Emotional Engine. According to this signal, the Emotional Engine updates the internal virtual world of the game program within the video frame rate. Many physical equations need to be solved to determine the behavior of the character in the game world. After this is determined, the calculated object position is transformed according to the viewpoint, and a drawing command sequence (display list) is generated. When the graphics synthesizer receives the display list, it draws the primitive shape based on connected triangles on the frame buffer. The contents of the frame buffer are then converted from digital to analogue, and the video image appears on the TV. Finally, the Sound Processor is in charge of sound card thing, it outputs 3D digital sound using AC-3 and DTS. This is the overview of PlayStation 2 working procedure.
2.3 Comparison
Compare Figure 2.1 and Figure 2.2, we can see that the PC’s architecture is far more complex than that of PlayStation 2’s. There are many reasons. PC has more devices has to care. For instance, PlayStation’s I/O processor, which is act as the same role as the system controller bus in PC, the chief responsibility of this chip is to manage the different devices attached to the PS2. 2 PlayStation controller port, and MagicGate-compatible memory card interface, 2 USB ports, and a full-speed 400Mbps IEEE 1394 port, which are much less than PC. The other main reason is processor’s speed increased much faster than other devices; the devices themselves had uneven speed increments as well. In general, PlayStation 2 has simpler architecture and less components and devices.
3. ALL ABOUT PROCESSORS
3.1 Pentium 4 Processor
Pentium 4 adopts Intel’s 7th generation architecture. We can see in detail from the diagram below. Since the birthday of PlayStation 2 waiting for exploring was 4th March 2000, when Pentium 4 was not published yet. It is unfair to PlayStation 2. However, Pentium 4 is the most popular processor in the present, and PlayStation 2 is globally the most popular game console, whatever.
Figure 3.1: Pentium 4 processor architecture
Since the previous generation architecture (Pentium III) Intel began to use hybrid CISC/RISC architecture. The processor has to accept CISC instructions, because it has to be compatible with all current software (most software is written using CISC instructions). However, Pentium 4 processes RISC-like instructions, but its front-end accepts only CISC x86 instructions. A decoder is in charge of the translation. Intel doesn’t create the path for programs using pure RISC instructions.
CISC instructions are rather complex, decoding one may cost several clock cycles. In Pentium III era, once a CISC instruction needed to be processed several times (i.e. a small loop), the decoder had to decode the instruction again and again. In Pentium 4 this situation has been improved by replacing Pentium III’s L1 instruction cache to Trace Cache, which is placed behind the decoder. The trace cache ensures that the processor pipeline is continuously fed with instructions, decoupling the execution path from a possible stall-threat of the decoder units. After decoding stage, Intel introduces the Renamer/Allocator unit to change the name and contents of 32-bit CISC instructions of the registers used by the program into one of the 128 internal registers available, allowing the instruction to run at the same time of another instruction that uses the exact same standard register, or even out-of-order, i.e. this allows the second instruction to run before the first instruction even if they mess with the same register.
The other big advance of Pentium 4 is its SSE2 - The New Double Precision Streaming SIMD Extensions. 128-bit SIMD package offers 144 strong instructions. Intel prepares two SIMD instruction units for Pentium 4 (64-bit each), one for instructions, and the other for data. Let’s recall Section 1.3, Pentium 4’s 128-bit SIMD extension is Intel’s efforts for meeting the future requirements for multimedia implementations. Because of that, video, games implementation capability gained the drastic enforcement.
Pentium 4’s pipeline is the most disputable place. When it was announced, 20-stage pipeline surprised a lot of people. Intel did so because the more stage pipeline can increase the clock rate of processor. However, once the pipeline does not contain the information what processor need, the pipeline refill-time is going to be a long wait. In fact, Pentium 4 is only faster than Pentium III because it works at a higher clock rate. Under the same clock rate, a Pentium III CPU would be faster than a Pentium 4.
Figure 3.2: Pentium 4 Pipeline
The scheduler is a heart of out-of-order engine in Pentium 4. It organizes and dispatches all microinstructions (in other words, uops) into specialized order for execution engines.
Figure 3.3: Pentium 4 scheduler
Four kinds of schedulers deal with different kinds of microinstructions for keeping the processor busy all the time. The ports are Pentium 4’s dispatch ports. If you read the diagram carefully, you can see Port 1 and Port 0 each is assigned a floating-point microinstruction, Port 0 is assigned Simple FP Scheduler (contains simple Floating-point microinstructions) and Port 1 is assigned Slow / Floating Point Scheduler (contains complex floating-point microinstructions). Port 0 and Port 1 also accept the microinstructions came from Fast Scheduler. For the floating point microinstruction may run several clock cycles, Pentium 4’s scheduler monitor decides to transfer the microinstruction to Port 1 if Port 0 is busy, and vice versa. Port 2 is in charge of Load microinstructions and Port 3 deals with Store microinstructions.
3.2 PlayStation 2’s Emotion Engine
PlayStation 2’s designers focus deeply on the purpose of 3D games. At the same time, they had to ensure it was completely compatible with DVD video. For performing 3D games well, PlayStation 2 has to possess perfect vision and audio functions. Emotion Engine acts as the role of Geometry calculator (transforms, translations, etc), Behavior/World simulator (enemy AI, calculating the friction between two objects, calculating the height of a wave on a pond, etc). It also in charge of a secondary job of Misc. functions (program control, housekeeping, etc). In general, Emotion Engine is the combination of CPU and DSP processor.
Figure 3.4: The architecture of Emotion Engine
The basic architecture of Emotion Engine is show in Figure 14. The units are composed of
(1) MIPS III CPU core
(2) Vector Unit (two vector units, VU0 and VU1)
(3) Floating-Point Coprocessor (FPU)
(4) Image Processing Unit (IPU)
(5) 10-channel DMA controller
(6) Graphics Interface Unit (GIF)
(7) RDRAM interface and I/O interface.
Something interesting in the diagram you may have noticed. First, inside the Emotion Engine, there is a main bus connects all components for data communication. However, between MIP III core and FPU, VU0 and MIP III, VU1 and GIF, there are dedicate 128-bit buses connect them. Second, VU0 and VU1 have certain relationship shown in the diagram. This design extremely enhanced the flexibility of programming with Emotion Engine.
MIPS III Core connects with the FPU and VU0 directly with the dedicated buses. The pipeline of MIPS III is 6-stage. The MIPS III is the primary and controlling part, VU0 and the FPU are coprocessors to MIPS III. They compute the behavior and emotion of synthesis, physical calculations, etc For example, in a football game, the flying orbits of the ball, the wind effect, the friction between ball and the ground need to be calculated. At the same time, 21 player’s AI needs to be implemented (the last player is controlled by the user), the activity, the lineup, etc. After the calculation, MIPS III core sends out the display list to GIF.
VU1 has a dedicated 128-bit bus connected to GIF, which is the interface between GS (Graphics Synthesizer) and EE (Emotion Engine). VU1 can independently generate display list and send to GIF via its dedicated bus. Both of these relationships forms a kind of dedicate and flexible structure. The final goal of EE is generating display list and send to GS. The programmer can choose either programming two groups (MIPSIII + FPU + VU0 and VU1 + GIF) separately, send their display list in parallel, or programming purposely, making MIPS III + FPU + VU0 group as the “coprocessor” of VU1, for instance, generate physical and AI information then send to VU1, VU1 then produces corresponding display list. The diagram below shows the two programming methods.
(a) (b)
Figure 3.5: Two programming methods of Emotion Engine
MIPS ISA is an industry standard RISC ISA that found in applications almost everywhere. Sony’s MIPS III implementation is a 2-issue design that supports multimedia instruction set enhancements. It has
(1) 32, 128-bit general purpose registers
(2) 2, 64-bit integer ALUs
(3) 1 Branch Execution Unit
(4) 1 FPU coprocessor (COP1)
(5) 1 vector coprocessor (COP2)
What I really want to cover are two vector processors, VU0 and VU1. This is the main reason why PlayStation 2 is powerful.
VU0 is a 128-bit SIMD/VLIW design. The main job of VU0 is acting as the coprocessor of MIPS III. It is a powerful Floating-point co-processor; deal with the complex computation of emotion synthesis and physical calculation.
The instruction set of VU0 is just 32-bit MIPS COP instructions. But it is mixed with integer, FPU, and branch instructions. VIF is in charge of unpacking the floating-point data in the main bus to 4 * 32 words (w, x, y, z) for processing by FMAC. VU0 also possesses 32 128-bit floating-point registers and 16 16-bit integers.
VU0 is pretty strong. It is equipped with 4 FMACs, 1 FDIV, 1 LSU, 1 ALU and 1 random number generator. FMAC can do the Floating-Point Multiply Accumulate calculation and Minimum / Maximum in 1 cycle; FDIV can do the Floating-Point Divide in 7 cycles, Square Root in 7 cycles, and Inverse Square Root in 13 cycles. In fact, as the coprocessor of MIPS III, VU0 only uses its four FMACs. However, VU0 doesn’t have to stay in coprocessor mode all the time. It can operate in VLIW mode (as a MIPS III coprocessor, VU0 only takes 32-bit instructions. In VILW mode, the instruction can be extended to 64-bit long). By calling a micro-subroutine of VLIW code. In this case, it splits the 64-bit instruction it takes into two 32-bit MIPS COP2 instructions, and executes them in parallel, just like VU1.
VU1 has very similar architecture than VU0. The diagram below is the architecture of VU1 possesses all function that VU0 has, plus some enhancement. First, VU1 is a fully independent SIMD/VLIW processor and deal with geometry processing. Second, VU1 has stronger capability than VU0: it has a 16K bytes’ instruction memory and a 16K bytes’ data memory, which VU0 only has 4K bytes each. VU1 acts as the role of geometry processor; it burdens more instructions and data to be computed. Third, VU1 has three different paths to lead its way to GIF. It can transmit the display list from 128-bit main bus, just as VU0 + CPU + FPU do; or it can transmit via the direct 128-bit bus between its VIF and GIF; the last one is quite interesting, the path comes out from the lower execution unit (which I will talk about later) and goes directly to GIF. Three individual paths ensure two main problems of PC 3D game programming will not happen: first, the bottleneck of bus bandwidth; second, the simplex way of programming.
Figure 3.6: The architecture of VU1
VU1’s VIF does much more than that of VU0 does. The VIF takes and parses in which Sony called 3D display list. The 3D display list constructs of two types of data: the VU1 programming instructions (which goes to Instruction memory) and the data that the instruction deal with (which goes to Data memory). The instruction itself can be divided into two units, Upper instruction and Lower Instruction, which directly operate on two different execution units, Upper execution unit and Lower execution unit. The 64-bit VLIW instruction can be used to deal with two operations in parallel. Recall that VU0 possesses the same function but most of time it acts only as the coprocessor of MIPS III, this mode can only operate 32-bit SIMD instructions. Programmers also rarely ask VU0 to do the same thing what VU1 is good at.
3.3 Comparison
I strongly agree if you think Emotion Engine is more flexible than Pentium 4. The design of Emotion Engine is completely around the performance of 3D games. Two vector units, VU0 and VU1, contribute a lot for the game performance. Pentium 4 architecture is straight, you can trace the path of data from the very beginning, and soon you will be able to know how Pentium 4 works easily. For Emotion Engine, except you are the game designer, you will never know exactly.
I did not put too much digits in this section, the comparison of digits does not make sense at all. The comparison between two PC processors depends on digits, because they are the same kind and work in the same situation. For game consoles, without the burden of compatibility, the designers think a lot for the perfect cooperation. This would results in better performance, plus less cost. Unfortunately the programmers don’t think it is a good idea, it cost them quite a lot of time to investigate the processor to figure how it works.
4. BUSES AND CACHEING
4.1 PC Motherboard
While multimedia processing requires massive quantities of data to move rapidly throughout the system, the speed difference between processor and external devices is the main bottleneck of PC. Processor companies like Intel have put a lot of energy into getting the rest of the system components to run faster, even if other vendors provide these components. Improving the performance of motherboard is a good idea. Figure 4.1 is the main structure diagram of GIGABYTE GA-8TRX330-L Pentium 4 Motherboard. The bandwidth between Processor and system controller, main memory and system controller has reached to equally incredible 6.4GB/S. However, the latency of memory is still impossible to remove. Here I want to talk something about the processor caching mechanism.
In the present, motherboard’s FSB (Front Side Bus) frequency has over 800 megahertz. However, it is slower than that of Pentium 4, which is over 3 gigahertz. Processor runs at a multiple of the motherboard clock speed, and is closely coupled to a local SRAM cache (L1 cache). If processor requires data it will fist look at L1 cache. If it is in L1 cache, the processor read the data at a high speed and no need to do the further search. If it is not, sadly processor has to slow down to the motherboard clock speed (what a drastic brake!) and contact to system controller. System controller will check if L2 cache has the required data. If has, the data is passed to processor. If not, processor has to access the DRAM, which is a relatively slow transfer.
4.2 About PlayStation 2’s buses and caching.
Recall Figure 2.2, we can see 32-bit interfaces between processor and I/O Processor, main memory and I/O Processor, which can achieve 3.2GB/S bus speed. Although slower than Pentium 4, Emotion Engine itself is relatively slow as well, 300MHz MIPS III processor. However, PlayStation 2’s 32-bit interface, 10-channel DMAC, 128-bit internal bus, and small cache memory group to an incredible caching condition. Any data necessary can be store or download in time. This strategy takes 90% of DMA capability. It makes the latency which main memory generates is acceptable for Emotion Engine.
4.3 Comparison
This time we can talk about digits some more. Let’s see a Pentium 4’s cache memory
L1 trace cache: 150K
L1 data memory: 16K
L2 memory: 256K ~ 2MB total: 422~2204K
Let’s see PlayStation 2 next
VU0 data memory: 4K
VU0 instruction memory 4K
VU1 data memory 16K
VU1 instruction memory 16K
MIPS III data memory: 2-way 8K
MIPS III instruction memory: 2-way 16K total: 64K
Contrast to Pentium 4, the cache memory of PlayStation 2 is too small. Its capability is indeed ‘weak’ in the present. Pentium 4 is able to hold more data and does more computations in parallel. However, PC architecture hasn’t been improved along with the processor. No matter how Pentium 4 fast is, present bus architecture is never going to perform Pentium 4 100% capability. PlayStation 2 achieves a nearly perfect structure and mechanism, which helps it exert as much as it can (or maybe I should say because Pentium 4 is too fast, the memory speed is relatively too slow). Besides, it remarkably low down the cost, you can afford a PlayStation 2 plus a controller with the same price of a single Pentium 4 chip.
5. VIDEO PERFORMANCE
5.1 Comparison of performance between PC and PlayStation 2
Figure 5.1 Need for Speed Most Wanted (PlayStation 2) 2006 by EA GAMES
PlayStation 2 Graphics Synthesizer (GS)
· 150 MHz (147.456 MHz)
· 16 Pixel Pipelines
· 2.4 Gigapixels per Second (no texture)
· 1.2 Gigatexels per Second
· Point, Bilinear, Trilinear, Anisotropic Mip-Map Filtering
· Perspective-Correct Texture Mapping
· Bump Mapping
· Environment Mapping
· 32-bit Color (RGBA)
· 32-bit Z Buffer
· 4MB Multiported Embedded DRAM
· 38.4 Gigabytes per Second eDRAM Bandwidth (19.2 GB/s in each direction)
· 9.6 Gigabytes per Second eDRAM Texture Bandwidth
· 150 Million Particles per Second
· Polygon Drawing Rate:
· 75 Million Polygons per Second (small polygon)
· 50 Million Polygons per Second (48-pixel quad with Z and Alpha)
· 30 Million Polygons per Second (50-pixel triangle with Z and Alpha)
· 25 Million Polygons per Second (48-pixel quad with Z, Alpha, and Texture)
· 18.75 Million Sprites per Second (8 x 8 pixel sprites)
Figure 5.2 Needs for Speed Most Wanted (PC) 2006 by EA GAMES
PC Graphics Chip RADEON X300 SE PCI Express
· Bus type PCI Express (x16 lanes)
· Maximum vertical refresh rate 85 Hz
· Display support Integrated 400 MHz RAMDAC
· Display max resolution 2048 x 1536
· Board configuration
· 64 MB frame buffer
· Graphics Chip RADEON X300 SE PCI Express
· Core clock 325 MHz
· Memory clock 200 MHz
· Frame buffer 64 MB DDR
· Memory I/O 64 bit
· Memory Configuration 4 pieces 8Mx16 DDR
· Board configuration
· 128 MB frame buffer
· Specification Description
· Graphics Chip RADEON X300 SE PCI Express
· Core clock 325 MHz
· Memory clock 200 MHz
· Frame buffer 128 MB DDR
· Memory I/O 64 bit
· Memory Configuration 4 pieces 16M x 16 DDR
· Memory type DDR1
· Memory 128 MB
· Operating systems support Windows? 2000, Windows XP, Linux XFree86 and X.Org.
· Core power 16 W (Max board power)
From the data we can see. GS is too weak, contrast to low-level video card of PC. However, the performance of PlayStation is not too that bad. I don’t want to analyze data here. What I am interested to discuss is about the performance itself.
Let’s see Figure 5.2 in detail. Texture is very clear and exquisite. This is what big video memory offers. The tree leaves in distance need a lot of polygons to build. The video card itself is low-level; possess no special effect for the game rendering. No refection and other sparking place can be found. In general, the game performance is only ok.
Figure 5.3 PC game rendering related architecture
Now let’s see PlayStation 2’s performance, which is in Figure 5.1. We see a good image. If you look the image in detail, you may found the mountain beside the road is weird: the shape of mountain is not that nature, like some spectrum graphics. This is done by VU1, which draws the Bezile, build 3D graphic based on the curve. Although not good enough, how many people will actually notice that when dashing at over 200km/h with his virtual car? VU1 does a lot of job like that and it could generate a lot of shapes without too many polygons to build. Now let’s see the car, the refection of cars is true reflection (which means it is not fake texture pretended to be the reflection), we can distinguish the mountains behind, however very blur. The whole image is not as clear as Figure 5.2 because the limitation of GS’s video memory (4M). However, this image is good enough for most PlayStation 2 players.
5.2 Some more about the video performance
Although Pentium 4 has enough capability to process image real time, the way of implementing games is still no change. The video card read the content of texture into its local memory card, the processor only deal with the data and instructions. After the calculation, the processor stores the display list (a list, recorded with the details of all elements, for instance, one single polygon’s position and texture code) back to the main memory. Video card then access the lists and process them, generate picture, transfer to analogue signal and output. Most special effects depend on the video card. So, no good card, no good performance.
Let’s see figure 2.2, we will see there is no direct connection between GS and main memory. At the PC’s point of view, 4MB video-memory is not enough to show a single frame with 1024*768 pixels. How is PlayStation 2 able to perform like that? The answer is bus. So we come back to section 4 again. The specialized display list (which Sony called 3D display list) is directly sent to GS, along with the required texture. GS has a huge bandwidth (3.8GB/S), its local memory can work as fast as it is (maybe it is more suitable if we call the memory as cache). GS itself supports only a few special effects. However, this situation can be improved by the simulation calculations finished by Emotion Engine… Again, PlayStation 2’s elegant design makes its all components work as a whole.
6. CONCLUSION
Hopefully you have got the idea of how PlayStation 2 and PC architecture differ. Let’s go through it again.
General architecture. PCs are more complex to read, but easier to implement. The system bus directly manages all devices inter-communications. PlayStation 2’s is easy to read, but much harder to implement. The communication between each other is convenient.
Processor architecture. The trend of processor architecture design is meeting the requirement of multimedia. Both PC’s Pentium 4 and PlayStation 2’s Emotion Engine are qualified to run multimedia applications efficiently. Pentium 4 is much stronger than Emotion Engine, but the architecture is very ‘straight’ and has to do extra jobs of translating instructions to be compatible with current applications. Emotion Engine has no this burden, the specialized 3D game performance design make it easy to handle complex calculation jobs with relatively low clock rate.
Buses and Caching. PC has classic bottlenecks and there is no way to overcome it. Current PC buses and cache has improved a lot by increasing the bandwidth and cache volumes, but the latency of main memory cannot be solved. PlayStation 2 works on nearly full load; perfect coordination between components is almost achieved.
Video. Although Pentium 4 can run perfectly on multimedia applications, the PC game developers don’t think so. They still stick to push the texture and other data into the video memory for one time. The awkward situation is, when you want to update your PC for high requirement games, the first component came into your mind must be the video card but processor. It is impossible to ask PlayStation 2 players to update. Emotion Engine is in charge of many jobs what PC’s video card does. The good condition of data transmission makes it is possible to implement ‘true’ multimedia processing in games, that is treating game image as media streams, no need to supply huge data storage to hold that.
Purpose: PC’s general—purpose VS PlayStation 2’s 3D game rendering purpose.
PlayStation 2 is 6 years old now. According to the principle of game console life expectance, it is time to hand the baton to its offspring, PlayStation 3. It is a successful game console of Sony. Contrast to PC, it is too weird, but all its weird compositions seemed so reasonable as well. PC’s architecture is classical; all components have its space for upgrade. Maybe it is too early to say the architecture should evolve. However, PlayStation 2’s architecture gave us a good lesson. If you only were interested in games, you should buy a PlayStation series, not a PC. At least, you need not worry about upgrading your components for the next game. Special architecture can make it becomes the best in specialized region.
7. REFERENCE
[1] William Buchanan and Austin Wilson, “Advanced PC Architecture”, ISBN: 0 201 39858 3
[2] John L. Hennessy and David A. Patterson, “Computer Architecture—A Quantitative Approach”, ISBN: 1 55890 724 2
[3] Keith Diefendorff and Pradeep K. Dubey, "How Multimedia Workloads Will Change Processor Design." Computer, September 1997
[4] Jon "Hannibal" Stokes Sound and Vision: A Technical Overview of the Emotion Engine Wednesday, February 16, 2000
[5] K. Kutaragi et al "A Micro Processor with a 128b CPU, 10 Floating-Point MACs, 4 Floating-Point Dividers, and an MPEG2 Decoder," ISSCC (Int’l Solid-State Circuits Conf.) Digest of Tech. Papers,Feb. 1999, pp. 256-257.
[6] Jon "Hannibal" Stokes “SIMD architectures”
arstechnica.com/articles/paedia/cpu/simd.ars
[7] “Graphics Synthesizer – Features and General Specifications”
arstechnica.com/cpu/1q99/playstation2-gfx.html
[8] “The Technology behind PlayStation 2”
ieee.org.uk/docs/sony.pdf
[9] Michael Karbo,“PC Architecture“
karbosguide.com/books/pcarchitecture/start.htm
[10] Gabriel Torres, “Inside Pentium 4 Architecture”
hardwaresecrets.com/article/235/1
[11] Thomas Pabst, “Intel’s new Pentium 4 Architecture”
tomshardware.co.uk/2000/11/20/intel/
[12] KuaiLeDaYuShu, “Video Card Parameters Analysis”
blog.yesky.com/Blog/joyelm/archive/2005/07/30/253803.html
[13]Howstuffworks “How PlayStation 2 Works”
entertainment.howstuffworks.com/ps21.htm
引言
攀枝花市，四川省唯一以花命名的城市，被稱作陽光花城，座落在四川西南角，金沙江和雅礱江交匯處。自1965年建市以來，城市建設已形成規模，旅游資源獨具特色：獨特的自然地理環境、獨具風味的飲食，濃郁的少數民族民俗風情文化，成為獨樹一幟的旅游品牌，成為攀枝花市對外開放的重要組成部分。
旅游文化的翻譯工作是使對外宣傳資料發揮作用的重要環節， 也是一個城市對外交流水平和人文環境建設的重要體現。如何讓攀枝花走向世界、讓世界了解攀枝花， 有效開展招商引資、擴大對外交流和合作起到了積極作用。在這種情況下，針對目前攀枝花市獨特旅游資源的英譯問題進行分析、研究，將極大地促進攀枝花的對外交流合作和提高城市的整體形象。但是由于中英旅游文本中的文化差異表現在其不同的審美、價值觀及風俗習慣等中英旅游文本在提供信息方面亦有不同的側重點。因此，在功能理論的指導下，結合中英旅游文本的不同點，，旅游文本的翻譯應以游客為中心，以傳播中國文化為導向，最終達到旅游文本的誘導目的?？梢圆扇∠鄳姆g策略：直譯、增譯、省譯、類比等，以期增強旅游文本譯文的可讀性，最終有效實現譯文的預期功能和目的。
一、攀枝花特色地理地貌的英譯
攀枝花地處攀西裂谷中南段，屬浸蝕、剝蝕中山丘陵、山原峽谷地貌，山高谷深、盆地交錯分布，地質構造復雜，森林覆蓋面積大，喀斯特地貌分布廣，裂谷、溫泉、溶洞、瀑布和河流比比皆是，為旅游事業的發展提供了資源基礎。對于對于攀枝花特色地理地貌的英譯方面，張沉香（2007）對于術語的國際化， 提出應“適當加大音譯比例”，“促進國際合作和科技發展”。
音譯不僅能夠達到簡潔和透明的作用，還是保存源語文化的最佳途徑。尊重術語體現的文化而采用音譯的翻譯方法也是現代術語翻譯的一個趨勢。以攀枝花地理地貌“喀斯特”為例，就是采用的音譯方法現已被學界多接受，然而它卻曾被中國學界采用意譯的方法改譯為“巖溶”。另一個類似的例子是世紀初由中國學者確定的“天坑”，即西方地理學學術話語中的“特大型塌陷漏斗”所描述的地理樣貌，在攀枝花也是數量眾多，大小不一。2005 年起，“天坑”這一定名獲得了國際喀斯特學術界的一致認可，漢語拼音 “tiankeng”開始國際通用“喀斯特”在中國和 “tiankeng”在國際學界的最終被接受，這體現了兩個屬于名詞文化內涵的保留，以及音譯在學術文化界的認同。
攀枝花非常有名的“格薩拉生態旅游區”主景區距瀘沽湖116公里，距麗江376公里，沿省道216線（稻攀路）前行可達稻城、亞丁，景區景觀由天坑地漏、巖溶景觀、高山草甸和彝家風情等組成。關于“格薩拉生態旅游區”的英譯資料“Gesala Ecotourism Area as a part of the Golden Triangular Tourism Area of Daocheng， Lijiang and Panzhihua is located at the juncture of Sichuan and Yunnan Provinces.”該譯文首先介紹了格薩拉生態旅游區的地理位置位于稻城，麗江和攀枝花旅游金三角，位于川滇兩省的交接處。 “ It is not only the south gate of the Great Shangri-la of China， but also an important component of the Sunshine Ecotourism Area in west Panzhihua City.” 此句則強調了格薩拉生態旅游區的重要性，為中國大香格里拉的南大門， “the south gate”則運用了英語中隱喻的修辭手法 “metaphor” ，非常生動形象。
Anothermajorareaofdebateintherealmofmacroeconomicsdealswiththebudgetdeficit.Therearenumerousquestionsthatsurroundthebudgetdeficitdebate.Forinstance,shouldthebudgetbebalanced?Whatistheburdenofthenationaldebt?Whatarethelong-termeffectsofanunbalancedbudget?Theanswerstothesequestionsdivideeconomists.
ThisSparkNotecoverstwomajoreconomicpolicydebatesthatrelatedirectlytomoneyandtotheeconomy.Thesedebatesareimportantsincetheyoftendivideeconomists.Similarly,byunderstandingthesedebates,itispossibletoviewthecomplexityofmacroeconomicpolicyintherealworld.Whilemacroeconomictheoryseemsratherblackandwhite,theapplicationofthistheorytotherealworldisnowherenearthissimple.
TheFedandthegovernmentusedifferenttoolstosteertheeconomy.Recallthatmonetarypolicy,thetoolboxoftheFed,includesperformingopenmarketoperations,andchangingboththereserverequirementandthefederalfundsinterestrate.Recallalsothatfiscalpolicy,thetoolboxofthegovernment,includeschangingbothtaxesandgovernmentspending.
Allofthesetoolscanbecontrolledactively.Thatis,iftheFedorthegovernmentdecidetouseexpansionarypolicy,theycansimplyselectatoolfromthepolicytoolboxanduseit.Inthisway,activepolicyisdefinedasactionsbytheFedorbythegovernmentthataredoneinresponsetoeconomicconditions.Thatis,theFedorthegovernmentchoosetorespondtosomethingintheeconomybyundertakingaspecificpolicy.Thisisalsocalleddiscretionarypolicy.
Activepolicy,whilesimple,isopentoanumberofdifficulties.BecauseitreliesontheactionsandexperiencesofthepolicymakersintheFedandinthegovernment,theweaknessesorprejudicesofthesepolicymakerscanbetranslatedintoofficialeconomicpolicy.Forinstance,duringelectionyears,acentralbankermaypursuepolicythatenablestheeconomytogrowintheshortrun,regardlessofthelong-termeffects,inordertohelpacandidate.Ontheotherhand,thecentralbankermaycontracttheeconomytohurtacandidate.Similarly,itwouldbepossibleforthepolicymakerstopursuepoliciesthatachievetheirselfishendsratherthanthosethatarebestfortheeconomyatlarge.Finally,withactivepolicy,policymakerscansayonethinganddoanother.Theremaybebenefitstomakingthepublicbelievethatsomethingdifferentisoccurringintheeconomyratherthanwhatactuallyisoccurring.Forinstance,iftheFedwantstoincreaseinvestment,itcouldusedeceptionbyclaimingthatitraisedinterestrateswhilenotactuallydoingso.Inthisscenario,privateinvestorswouldsavemorebutinvestmentwouldremainattheoldlevelorevenincrease.Thus,itisreasonabletoclaimthatactivepolicyleavesmonetarypolicyandfiscalpolicyopentonotonlyaccidentalhumanerrorbutalsotomaliciousandself-servingacts.
二、依綱扣本，中考采用三階段四板塊循環滾動的復習模式
根據《英語課程標準》和《英語中考指南》，三階段指復習時間分為三個階段，四板塊指單元梳理板塊、專項訓練板塊、綜合訓練板塊和聽、說、讀、寫能力訓練板塊，它們互相融合互相促進，使知識和能力水平不斷循環提升。第一階段單元梳理板塊主要是梳理初中階段所學的全部的語言知識。牛津英語教材按照話題———結構———功能———情景———任務體系以單元形式編排，所以梳理語言知識以單元作板塊來整體復習較合理。按教材順序以話題和任務為主線，以及他們和功能、語法項目的關系提前分門別類的梳理，歸納四會單詞、重點詞組、重點句型、語法和課本對話等知識，匯編成講義發給學生，使學生腦子中有清晰知識體系網絡圖。第二階段專項訓練復習是對針對名詞、冠詞、非謂語動詞、并列句和復合句等作專項的訓練。此階段的任務主要通過語法線來鞏固、深化課本英語知識。第三階段綜合訓練板塊任務主要是通過專項題型和模擬測試來全面培養學生綜合應試能力水平。綜合訓練也可從英語總復習一開始時就要有計劃安排，如一個星期做一套完整的綜合試卷或專項題，以便培養整體復習英語的意識。聽、說、讀、寫能力訓練板塊始終貫穿在整個三個階段里，要反復有層次地訓練，每周要固定時間，保證訓練次數和質量，同時做好點撥和評析，傳授各種方法和技巧，使知識和能力形成互補，提高復習效率。
三、分層指導，在統一練習同時重視分層的作業布置
英語總復習階段學生的英語水平已經參差不齊，根據知識掌握程度和學習品質可以分成優秀生，中等生和后進生，其中后進生的英語水平還不如七年級學生的英語水平。那么教師既不能放棄某些學生，也不能一個層次要求所有的學生。只有根據學生個體的學情分層指導和要求才為上策。首先英語語言知識點分層要求可從教材自身出發，對于每個單元，細到梳理知識點，在此基礎上進行“淘金”活動，將知識點梳理成金字塔形，將不同的知識點對應于不同層次的學生，分層次分解知識點，對相應層次的學生提出相應的需求。其次要引進競爭機制來分層次優化，根據每位學生的能力，制訂標準分，進行獎勵，使他們個個有對手，人人有復習目標，人人有危機感，把學習積極性最大限度地調動起來。最后對于后進生特別要多進行情感關懷，根據學生不同情況幫助他們找出名自的薄弱環節，采取人盯人辦法，一方面進行面對面輔導；另一方面認真面批他們的練習和試卷，分析他們的錯誤原因，幫助他們寫出正確答案。這樣每個層次的學生都相應到達應有的復習水平，提高了復習效率。
【1】ZeigerM.Essentialsofwritingbiomedicalresearchpapers.NewYork：McGraw-Hill，Inc，1991.257-283
【2】LawrenceJ.Appel，etc.ComparativeEffectivenessofWeight-LossInterventionsinClinicalPractice[J].NewEnglandJournalofMedicine， 2011，365：1959-1968
【3】陳攻，李晶.醫護人員習得醫學英語專業詞匯方法淺析[J].護理學雜志，2008，23（1）：16-19
【4】何筑麗，國林祥.醫學英語寫作與翻譯[M].北京：高等教育出版社，2000
【5】任如意.醫學論文英語寫作的文體特點[J].實用兒科臨床雜志，2009，24（17）：1383-1384
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[2]Dawkins，Richard.TheSelfishGene[M].NewYork：OxfordUniversityPress，1976.
[3]陳琳霞.模因論與大學英語寫作教學[J].外語學刊，2008（1）：88—91.
[4]何自然.語言中的模因[J].語言科學，2005（6）：54—64.
[5]張穎、模因論對大學英語聽說教學的啟示[J].西安外國語大學學報，2009（3）：111—113.
參考文獻：
［1］Knoy，Ted，AnEditingWorkbookforChineseTechnicalWriters［M］.Hsinchu，Taiwan：CWebTechnology，2000.
［2］瓊·平卡姆（美）.中式英語之鑒［M］.外語教學與研究出版社，1998.
2.利用英語歌曲學習祈使句
祈使句是日常生活中用得最多、最口語化的句型?？衫玫倪@類歌曲很多，如Let’sgonow,Lookatmydoll,Let’ssinganddance,Ifyou’rehappy等等。這些歌曲的風格大多節奏明快、輕松活潑、動作感強，最適合小學生，也最受他們的歡迎。教師在教唱的過程中，輔之相應的動作和豐富的表情，課堂上的氣氛頓時活躍起來。學唱這類歌曲的方法很多，如獨唱、合唱、分小組唱、男女對唱等，形式多樣。
3.利用英語歌曲幫助日常交流
這類歌曲很多，覆蓋面最廣，常常涉及到五個“W”—who/what/where/when/why和一個“h”---how，如What’syourname?Howoldareyou?WhereisMickeyMouse?等。這類歌曲與課本內容聯系很密切，往往就是一節課的主要內容。但是，這些歌曲的歌詞也相對比較復雜，比較適合語音、語調和語感較好的中、高年級學生。
4．利用英語歌曲學習表達思想
在歌曲教學中，教師豐富的表情、生動的語言和多彩的道具，構成了一場場出色的歌舞劇。教師是出色的編導，而可愛的學生就成了出色的演員。
中圖分類號：H315 文獻標識碼：A
文章的主體是科技論文的核心部分，是主題思想的展開和論述。作者可根據需要在文章中加小標題，將主體內容分為幾個部分進行論述?？萍颊撐牡挠⑽膶懽魍ǔ０衙慷蔚闹黧w句（Topic Sentence）放在段落的第一句，全段圍繞主體句論述，定義與敘述是科技論文寫作中又一種常用的寫作方法。
一、定義（Definition）
（一）Introduction
When making a hypothesis（假說）or other statement， scientists must make sure that they will beunderstood by other researchers. Misunderstandings occur when there are different concepts of what is being discussed.
A definition answers the question， “What is it?” Sometimes a definition is necessary because a word or concept has more than one meaning. For example， whether carbon is a metal or nonmetal depends on how you define carbon. At other times， a definition is required because a term is being used in a special way. For example， physicists use the terms work and energy in ways that are more specific than their common meanings. A definition should be complete enough to include all the items in the category yet narrow enough to eliminate items that do not belong. The Greek philosopher Plato once defined man as a two-legged creature that has no feathers. The problem with Plato's definition was that it did not distinguish a man from other two-legged creatures without feathers. Communication between researchers is dependent on precise definitions of substances， concepts， processes， and ideas.
Greek philosopher Plato 希臘哲學家帕拉圖
（二）Sentence patterns
Sentence pattern 1:
An astronomer is a scientist whostudies the universe.
A barometeris an instrumentthat measures air pressure.
Conductionis a process by which heat is transferred.
A laboratoryis a place whereexperiments are performed.
Physicsis the study ofmatter and energy.
A volt is a unitfor measuring electrical pressure.
Sentence pattern 2:
Mercuryisa liquidmetal.
Asbestosis a fire-resistantmineral.
A dinosaurisa prehistoric reptile.
A monkeyis a small， long -tailedprimate.
（三）Application Examples
be 是
mean 意思是，意味著，意指
denote 表示，指
imply 意思是，意味著
be named 命名為，被稱為
Examples：
1. Printers are output devices.
打印機是輸出設備。
2. Multiprogramming means the existence of many programs in different parts of main memory at the same time.
多道程序意味著在主存儲器的不同部分同時存在著多個程序。
3. Data denotes a collection of facts that can serve as operands to computer program.
數據是指可作為計算機程序操作對象的集合。
4. A “system” implies a good mixture of integrated parts working together to form useful whole.
“系統”意指將協同工作各部分適當地綜合而成的一個有效的整體。
5. The first digital computer built in 1946 at the University of Pennsylvania was named ENIAC.
第一臺計算機是1946年在賓夕法尼亞大學建造的，命名為ENIAC。
二、敘述（Describing）
（一）Introduction
A description serves to introduce a scientist's view of the world. It may describe conditions， results of an experiment， chemical changes， physical movements， or what is seen through a telescope or microscope. A description may also tell the characteristics or distinctive features of an object―how it look， sounds， tastes， smells， works， or is produced.
The nature of something can be explained by describing it. For example， the concept of an atom is difficult to grasp from a definition alone， but a description of its appearance， detailing its structure and function， makes it easier to visualize.
（二）Sentence patterns
The Nile River is 4，145 miles long.
Mount Everest is 8，848 meters high.
The Dead Sea is 11 miles wide.
The Nile River has a length 4，145 miles.
The Sun has a surface temperature of 11，000°F.
The Grand Canyon has a depth of 5，500 feet.
The color of iodine is purplish black.
The texture of sand is rough and granular.
The orbits of planets are elliptical.
Pluto is relatively small.
Blue stars are extremely hot.
Copper salts are slightly blue in aqueous solutions.
（三）Application Examples
be是
be considered （to be） 被認為是，被看作
be known as 被稱為是，被認為是，即
be referred to as 稱為，叫做
be thought of as 被認為是
be regarded as 被認為是
Examples:
1.This ability to allow interrupts to interrupt previous interrupts service routines safely are referred to as nested interrupts.
允許某些中斷去中斷先前的中斷服務程序，并能正確運行的能力稱為嵌套中斷。
2.One of the most important characteristics of a computer is its capability of storing information in its memory long enough to process it.
計算機最重要的特性之一就是具有這樣一種能力，即在它的存儲器中保存信息時間長到足以對這些信息進行處理。
3.In the majority of applications the computer's capability to store and access large amounts of information plays the dominant part and is considered to be its primary characteristic.
在大部分的應用中，計算機能夠存儲和訪問大量的信息這一特性，起了關鍵的作用，并被看成是計算機的主要特點。
二、商務英語會話中的語用范疇
語用范疇在商務溝通領域必不可少，如奧斯汀的言語行為理論、格萊斯的合作原則等。這些理論在商務英語會話中的作用不容忽視，對理論的理解和應用在相當大的程度上直接決定著溝通的成敗與否。言語行為理論始于西方，并由約翰·蘭肖·奧斯汀提出，該理論使得語用學研究進入新領域。奧斯汀的言語行為理論主要包括兩個方面：首先，講述語言單位及其意動功能；其次，談及了語言單位的主客體視角所導致的行為。例如，當中國商人和中亞國家進行貿易談判時，中國客戶表情如果表現得僵硬或者發出有言外之意的言辭，中亞商家將無法理解，因為在中亞國家里，面部表情所表達出來的意思占據著聽話人的主要判斷，而這一判斷如果失敗將直接導致言外之意的無法表達，在這一會話過程中就會出現雙方難以理解的問題。
1.語塊與語言表達
語塊有助于提高語言表達的流利性和準確性。語塊是語言使用中形成的習慣性語言構塊，使用者無需知道其內部結構就可以流利地表達，在交際時可以整體提取使用。Nattinger&DeCarrico指出，人們使用語言的流利度不取決于學習者大腦中存儲了多少生成語法規則，而在于存儲了多少語塊。另外，語塊大都是按照一定的語法規則生成的，交際時學習者不需特意注意語法結構。在商務活動交際過程中，學習者可以直接提取大腦中儲存的符合特定語境的語塊，靈活運用語塊，更順利地完成商務交際目的。
2.語塊與語用能力
語塊可以提高交際的得體性。因為每個語塊都有語用功能，表示同一功能的語塊以語義場(se－manticfield)的形式存在于大腦中，提取使用時根據交際語境、交際對象等具體情況，選取最合適的語塊。因此，語塊教學可以使學生獲得一定交際策略的能力，以保證交際的順利完成。正如Krashen(1978)指出的，學習者出于交際壓力的影響，必須記一些公式化的套語。為了編制出創造性的語言，他們必須記住許多現成的口頭話語以彌補第二語言規則的不足。通過掌握大量的語塊，增加學習者語言的儲備，使語言交流更順利。商務英語交際時，學生可以根據具體的商務語境、交際對象、交際時的主題等，選取合適的語塊來提高交際的得體性。
3.語塊與詞匯的記憶
語塊學習有助于提高學生的詞匯記憶與習得。語塊有利于詞匯的學習。首先，由于語塊是較大的詞匯構塊，甚至是完整的句子，它們就像不可分的“組塊”儲存在大腦詞庫中，容易自動檢索。另外，語塊作為整體在語言中出現的頻率較高，可確保語塊能自然地、不斷地得到循環。語塊高頻出現和語境依附的特征容易使學習者對學習內容產生“形式-語境-功能”的聯系，從而以整體形式習得與儲存。語塊意義是置于特定的語境，比脫離語境單獨背詞匯更容易記住，而且不容易遺忘。
二、基于語塊的商務英語教學方法
商務英語交際活動的順利進行很大程度上依賴于商務英語中的語塊現象。建立以語塊為紐帶的教學法是提高學習者商務英語能力的一個切實可行的方法。因此，可采取以下方法實施“語塊”教學法。
1.識別語塊
教學活動以語塊為中心。教師幫助學生了解語塊的特點、作用和類型，引導學生識別和區分語塊，激活學生的語塊意識，在學生潛意識中把語塊作為語言學習的最小單位。教學中教師應明確向學生指出不同商務體裁語篇中高頻出現的語塊，除了要求學生記憶并會使用教材中出現的語塊外，還可以結合語塊中的核心詞匯提供一些常規搭配，供學生反復操練，培養學生對語塊的辨別能力和敏感性。同時，教師可使用類比、歸納、同義、反義、形近等方法讓學生把新學到的語塊和之前學的詞匯或語塊建立起聯系，增強學生對詞匯學習的系統性，便于詞匯的記憶、儲存和提取，以提高學生的商務英語能力。
2.歸納語塊
了解了語塊的特點和功能后，教師可引導學生根據不同的語塊分類標準，將商務活動中不同語境中的語塊使用情況進行歸納分類。如商務寫作課程中的商務信函寫作，教師可引導學生根據不同信函的種類(如詢盤和報盤)歸納出其中每個環節的語塊使用情況。另外，教師可利用權威地道的商務英語信函例文指導學生進行商務英語信函的寫作，強化學生識別商務英語信函中的語塊意識，加強基于語塊的商務英語信函寫作。
