1、大学英语六级 104 及答案解析(总分：428.04，做题时间：132 分钟)一、Part I Writing (3(总题数：1，分数：30.00)1.For this part, you are allowed thirty minutes to write an open letter to the major of the city based on the following situation: You should write at least 150 words, and base your composition on the outline given below: 1近年来
2、，本市的空气污染情况越来越严重； 2你认为造成空气污染的主要污染源是哪些?应该采取哪些措施? 3呼吁所有市民积极行动起来，治理空气污染。 （分数：30.00）_二、Part II Reading C(总题数：1，分数：71.00)Programming languages Programming languages are how people talk to computers. The computer would be just as happy speaking any language that was unambiguous. The reason we have high lev
3、el languages is because people cant deal with machine language. The point of programming languages is to prevent our poor frail human brains from being overwhelmed by a mass of detail. Architects know that some kinds of design problems are more personal than others. One of the cleanest, most abstrac
4、t design problems is designing bridges. There your job is largely a matter of spanning a given distance with the least material. The other end of the spectrum is designing chairs. Chair designers have to spend their time thinking about human bodies. Software varies in the same way. Designing algorit
5、hms (运算法则) for routing data through a network is a nice, abstract problem, like designing bridges. Whereas designing programming languages is like designing chairs: its all about dealing with human weaknesses. Most of us hate to acknowledge this. Designing systems of great mathematical elegance soun
6、ds a lot more appealing to most of us than pandering to human weaknesses. And there is a role for mathematical elegance: some kinds of elegance make programs easier to understand. But elegance is not an end in itself. And when I say languages have to be designed to suit human weaknesses, I dont mean
7、 that languages have to be designed for bad programmers. In fact I think you ought to design for the best programmers, but even the best programmers have limitations. I dont think anyone would like programming in a language where all the variables were the letter x with integer subscripts. If you lo
8、ok at the history of programming languages, a lot of the best ones were languages designed for their own authors to use, and a lot of the worst ones were designed for other people to use. When languages are designed for other people, its always a specific group of other people: people not as smart a
9、s the language designer. So you get a language that talks down to you. Cobol (计算机通用语言) is the most extreme case, but a lot of languages are pervaded by this spirit. It has nothing to do with how abstract the language is. C is pretty low-level, but it was designed for its authors to use, and thats wh
10、y hackers like it. The argument for designing languages for bad programmers is that there are more bad programmers than good programmers. That may be so. But those few good programmers write a disproportionately large percentage of the software. Im interested in the question, how do you design a lan
11、guage that the very best hackers will like? I happen to think this is identical to the question, how do you design a good programming language? Give the Programmer as Much Control as Possible. Many languages (especially the ones designed for other people) have the attitude of a governess: they try t
12、o prevent you from doing things that they think arent good for you. I like the opposite approach: give the programmer as much control as you can. When I first learned Lisp (表处理语言), what I liked most about it was that it considered me an equal partner. In the other languages I had learned up till the
13、n, there was the language and there was my program, written in the language, and the two were very separate. But in Lisp the functions and macros I wrote were just like those that made up the language itself. I could rewrite the language if I wanted. It had the same appeal as open-source software. A
14、im for Brevity. Brevity is underestimated and even scorned. But if you look into the hearts of hackers, youll see that they really love it. How many times have you heard hackers speak fondly of how in, say, APL, they could do amazing things with just a couple lines of code? I think anything that rea
15、lly smart people really love is worth paying attention to. I think almost anything you can do to make programs shorter is good. There should be lots of library functions; anything that can be implicit should be; the syntax (句法) should be simple; even the names of things should be short. And its not
16、only programs that should be short. The manual should be thin as well. A good part of manuals (说明书) is taken up with clarifications and reservations and warnings and special cases. If you force yourself to shorten the manual, in the best case you do it by fixing the things in the language that requi
17、red so much explanation. Admit What Hacking Is. A lot of people wish that hacking was mathematics, or at least something like a natural science. I think hacking is more like architecture. Architecture is related to physics, in the sense that architects have to design buildings that dont fall down, b
18、ut the actual goal of architects is to make great buildings, not to make discoveries about statistics. What hackers like to do is make great programs. And I think, at least in our own minds, we have to remember that its an admirable thing to write great programs, even when this work doesnt translate
19、 easily into the conventional intellectual currency of research papers. Intellectually, it is just as worthwhile to design a language programmers will love as it is to design a horrible one that embodies some idea you can publish a paper about. How to Organize Big Libraries? Libraries are becoming a
20、n increasingly important component of programming languages. Theyre also getting bigger, and this can be dangerous. If it takes longer to find the library function that will do what you want than it would take to write it yourself, then all that code is doing nothing but make your manual thick. So I
21、 think we will have to work on ways to organize libraries. The ideal would be to design them so that the programmer could guess what library call would do the right thing. Are People Really Scared of Prefix Syntax? This is an open problem in the sense that I have wondered about it for years and stil
22、l dont know the answer. Prefix syntax seems perfectly natural to me, except possibly for math. But it could be that a lot of Lisps unpopularity is simply due to having an unfamiliar syntax. Whether to do anything about it, if it is true, is another question. What Do You Need for Server (服务器)-Based S
23、oftware? I think a lot of the most exciting new applications that get written in the next twenty years will be Web-based applications, meaning programs that sit on the server and talk to you through a Web browser. And to write these kinds of programs we may need some new things. One thing well need
24、is support for the new way that server-based applications get released. Instead of having one or two big releases a year, like desktop software, server-based applications get released as a series of small changes. You may have as many as five or ten releases a day. And as a rule everyone will always
25、 use the latest version. You know how you can design programs to be debug gable (调试器)? Well, server-based software likewise has to be designed to be changeable. You have to be able to change it easily, or at least to know what is a small change and what is a momentous one. Another thing that might t
26、urn out to be useful for server based software, surprisingly, is continuations. In Web-based software you can use something like continuation-passing style to get the effect of subroutines in the inherently stateless world of a Web session. Maybe it would be worthwhile having actual continuations, i
27、f it was not too expensive. What New Abstractions Are Left to Discover? Im not sure how reasonable a hope this is, but one thing I would really love to do, personally, is discover a new abstractionsomething that would make as much of a difference as having first class functions or recursion or even
28、keyword parameters. This may be an impossible dream. These things dont get discovered that often. But I am always looking for. （分数：71.00）(1).Designing algorithms (运算法则) for routing data through a network and designing bridges are both nice, abstract problems.（分数：7.10）A.YB.NC.NG(2).Since languages ha
29、ve to be designed to suit human weaknesses, it has to be designed for bad programmers.（分数：7.10）A.YB.NC.NG(3).Architecture is related to physics, so the actual goal of architects is to make discoveries about statistics.（分数：7.10）A.YB.NC.NG(4).Libraries are getting bigger and this can be dangerous for
30、programming languages.（分数：7.10）A.YB.NC.NG(5).The point of programming languages is to prevent our poor frail human brains from_.（分数：7.10）_(6).The argument for designing languages for bad programmers is that_.（分数：7.10）_(7).When I first learned Lisp (表处理语言). what I liked most about it was that it cons
31、idered me_.（分数：7.10）_(8).Hackers could do amazing things in APL with just_.（分数：7.10）_(9).If you force yourself to shorten the manual, in the best case you do it by_that required so much explanation.（分数：7.10）_(10).Web-based applications are programs that sit_and talk to you through a Web browser.（分数：
32、7.10）_三、Listening Comprehens(总题数：1，分数：15.00)A.He refused to drive her to the station.B.He is glad to drive her to the station.C.He forgot his driving license.D.He has a new car.A.The woman will pay by check.B.The woman will not make the purchase.C.The woman will pay by the credit card.D.The woman pr
33、efers the gift unwrapped.A.Call a friend.B.Work on his car.C.Take a taxi.D.Walk to work.A.They will sail to San Francisco.B.They will fly to San Francisco.C.They will drive to San Francisco.D.They will take a train to San Francisco.A.Its not important how he dances.B.Its too crowed to dance anyway.C
34、.If hes careful, no one will notice.D.No one knows the steps to the dance.A.Sailing a boat.B.Catching a worm.C.Fishing.D.Hanging clothes.A.She doesnt like the film.B.The film is hard to understand.C.She saw the film from beginning to end.D.She only saw the last part of the film.A.She is going to Haw
35、aii.B.She has traveled all over the world.C.She likes postcards.D.She is going on vacation.四、Section A(总题数：2，分数：10.00)A.The man wants to obtain an international drivers license that he can use both in the U. S. and in his country.B.The man wants to take a drivers test to get an Arizona drivers licen
36、se.C.The man wants to know whether he can use his international drivers license in Arizona.D.The man wants to fill out an application for an Arizona drivers license.A.Less than one year.B.Five years.C.Four years.D.Ten years.A.Fill out an application.B.Go back to the university to get his ID.C.Go to
37、see his friend.D.Take a written exam and an eve exam.A.Dont write the character reference for Alex.B.Dont tell the truth about Alex in the character reference.C.To go out and have coffee with her.D.To go to the restaurant with her.A.He likes kids and has worked in a childrens camp.B.He is lazy and i
38、mmature but good in a crisis.C.He quarrels with everyone he works with.D.He is immature and loves playing tricks on people.A.Alan thought Sally was too hard on Alex.B.Alan liked Alex very much and would write him a very good reference.C.Alan would turn down Alexs request.D.Alan could see something g
39、ood even in a very bad person.五、Section B(总题数：3，分数：10.00)A.Because men are seldom seen in the forest.B.Because tigers are afraid of something.C.Because men are not edible.D.Because men shout aloud.A.The man seems to have no back and from the side can barely be seen.B.The man is smaller than the tige
40、r itself.C.The man smells bad.D.The man looks very much like a deer.A.Because men are less likely to be well armed when they bend.B.Because men seem more obedient when they bend.C.Because men more closely resembles a medium-sized deer when they bend.D.Because men are cutting grass when they bend.A.R
41、eplacing the native corn with the hybrid corn.B.Replacing the hybrid corn with the native corn.C.Replacing the new type of corn with the traditional corn.D.Replacing the traditional corn with the native corn.A.Excellent quality.B.Large productivity.C.Good flavor.D.Both A and B.A.Because their wives
42、didnt like it.B.Because it wasnt good for cooking.C.Because their wives didnt like the flavor.D.All of the above.A.She was bored with her idle life at home.B.She was offered a good job by her neighbor.C.She wanted to help with the familys finances.D.Her family would like to see her more involved in
43、social life.A.Doing housework.B.Looking after her neighbors children.C.Reading papers and watching TV.D.Taking good care of her husband.A.Jane got angry at Bills idle life.B.Bill failed to adapt to the new situation.C.Bill blamed Jane for neglecting the family.D.The children were not taken good care
44、 of.A.Neighbors should help each other.B.Women should have their own careers.C.Man and wife should share household duties.D.Parents should take good care of their children.六、Section C(总题数：1，分数：10.00)The Pentagon is seeking congressional approval for development of a new weapon able to strike distant
45、 targets an hour after they are detected, a newspaper reported on Monday. The International Herald Tribune said the weapon would be a (36) 1version of the submarine-launched Trident-2 missile and be part of a presidents (37) 2when considering a preemptive (先发制人的) attack. The report quoted U.S. milit
46、ary officials as saying it could be used to hit (38) 3camps, enemy missile sites, suspected caches of weapons of mass (39) 4and other urgent threats. General James Cartwright, the head of the U.S. Strategic Command, said the system would allow U.S. forces to attack targets (40) 5and precisely and “l
47、imit the collateral damage“. The Pentagon would like the system (41) 6in two years, the report said. But the program has run into (42) 7from lawmakers concerned that it could increase the risk of an (43) 8nuclear war. Under the Pentagon plan, both and nuclear-tipped variants of the Trident-2 missile would be loaded on the same submarines. (44)“ 9,“ the newspaper quoted Senate Armed Services Committ
