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1.[单选题]What is the author’s main concern?

A.How to render automobiles pollution-free.

B.How to make smaller and safer automobiles.

C.How to solve the problem of traffic jams.

D.How to develop an automated subway system.

2.[单选题]What is the author’s attitude toward the future of autos?

A.Enthusiastic.

B.Pessimistic.

C.Optimistic.

D.Cautious.

3.[单选题]In an automated highway system, all the driver needs to do is ________.

A.keep in the right lane

B.wait to arrive at his destination

C.keep in constant touch with the computer center

D.inform the system of his destination by phone

4.[单选题]One significant improvement in the future car will probably be ________.

A.its power source

B.its driving system

C.its monitoring system

D.its seating capacity

5.[单选题]What provides autos with electric power in an automated highway system?

A.A rail.

B.An engine.

C. A retractable arm.

D.A computer controller.

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style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/B)Paper can be made from an almost endless variety of cellulose-based material which will include many woods, cottons and grasses or which papyrus is an example and from where we get the word “paper”. Many of these are very specialized, but the preponderance of paper making has been from soft wood and cotton or rags, with the bulk being wood-based.
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/ style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/C)In order to make wood into paper it needs to be broken down into fine strands. Firstly by powerful machinery and then boiled with strong alkalies such as caustic soda, until a fine pulp of cellulose fibers is produced. It is from this pulp that the final product is made, relying on the bonding together of the cellulose into layers. That, in a very small nutshell, is the essence of paper making from wood. However, the reality is rather more complicated. In order to give us our white paper and card, the makers will add bleach and other materials such as china clay and additional chemicals.
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/D)A further problem with wood is that it contains a material that is not cellulose. Something called lignin. This is essential for the tree since it holds the cellulose fibres together, but if it is incorporated into the manufactured paper it presents archivists with a problem. Lignin eventually breaks down and releases acid products into the paper. This will weaken the bond between the cellulose fibers and the paper will become brittle and look rather brown and careworn. We have all seen this in old newspapers and cheap paperback books. It has been estimated that most paper back books will have a life of not greater than fifty years. Not what we need for our archives.
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/E)Since the lignin can be removed from the paper pulp during manufacture, the obvious question is “why is it left in the paper?” The answer lies in the fact that lignin makes up a considerable part of the tree. By leaving the lignin in the pulp a papermaker can increase his paper yield from a tree to some 95%. Removing it means a yield of only 35%. It is clearly uneconomic to remove the lignin for many paper and card applications. It also means, of course, that lignin-free paper is going to be more expensive, but that is nevertheless what the archivist must look for in his supplies. There is no point whatsoever in carefully placing our valuable artifacts in paper or card that is going to hasten their demise. Acid is particularly harmful to photographic materials, causing them to fade and is some cases simply vanish!
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/F)So, how do we tell a piece of suitable paper or card from one that is unsuitable? You cannot do it by simply looking, and rather disappointingly, you cannot always rely on the label.  "Acid-free" might be true inasmuch as a test on the paper may indicate that it is a neutral material at this time. But lignin can take years before it starts the inevitable process of breaking down, and in the conditions it will speed up enormously.
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/G)Added to this, as I have indicated earlier, paper may also contain other materials added during manufacture such as bleach, china clay, chemical whiteners and size. This looks like a bleak picture, and it would be but for the fact that there are suppliers who will guarantee the material that they sell. If you want to be absolutely sure that you are storing in, or printing on, the correct material then this is probably the only way. Incidentally, acids can migrate from material to material. Lining old shoe boxes with good quality acid-flee paper will do little to guard the contents. The acid will get there in the end. 
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/ style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/H)Paper is also commonly made from cotton and rag waste. This has the advantage of being lignin-free, but because there is much less cotton and rag than trees, it also tends to be much more expensive than wood pulp paper. You will still need to purchase from a reliable source though, since even rag paper and card can contain undesirable additives.
style=margin: 0px; padding: 0px; color: rgb(51, 51, 51); font-family: 宋体; font-size: 14px; white-space: normal; background-color: rgb(255, 255, 255);/I)A reliable source for quality rag papers is a recognized art stockiest. Many water color artists insist on using only fine quality rag paper and board. The main lesson to learn from this information is that you cannot rely on purchasing archival materials from the high street. The only safe solution is to purchase from specialist suppliers. It may cost rather more, but in the end you will know that your important and valuable data and images have the best home possible.

1.[选词填空]If the lignin is removed from the paper, the paper will be more expensive.

2.[选词填空]In order to make white paper and card, the makers will add bleach.

3.[选词填空]Many paper producers will preserve lignin during manufacture, because leaving the lignin will make more paper from a tree.

4.[选词填空]Acid is particularly harmful to photographic materials.

5.[选词填空]Although free of lignin, paper made from cotton and rag waste can also cost more money than wood pulp paper because there is much less cotton and rag than trees.

6.[选词填空]There are a lot of materials which can be used for making paper, but the superiority ones are soft wood, cotton and rags.

7.[选词填空]The corn-flake packet is cheaper than high grade card.

8.[选词填空]During the whole manufacturing process, the final product is made from a pulp of cellulose fibres.

9.[选词填空]Lignin is essential for the tree but it will make paper easy to break.

10.[选词填空]What we can learn from “Paper from Rag” is that you had better buy archival materials from specialist suppliers.

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style=text-align: justify; style=text-align: justify; style=text-align: justify; style=text-align: justify; style=text-align: justify; style=text-align: justify;

1.[单选题]The aim of the voyages Maury was responsible for in the 1840s was ______.

A.to make some sounding experiments in the oceans

B.to collect samples of sea plants and animals

C.to estimate the length of cable that was needed

D.to measure the depths of the two oceans

2.[单选题]The proposal to lay a telegraph cable from Europe to America made oceanographic studies take on ______.

A.an academic aspect

B.a military aspect

C.a business aspect

D.an international aspect

3.[单选题] It was ______ that asked Maury for help in oceanographic studies.

A.the American Navy

B. some early intercontinental travelers

C.those who earned a living from the sea

D.the company which proposed to lay an undersea cable

4.[单选题]The aim of the voyages Maury was responsible for in the 1840s was ______.

A.to make some sounding experiments in the oceans

B.to collect samples of sea plants and animals

C.to estimate the length of cable that was needed

D.to measure the depths of the two oceans

5.[单选题]This passage is mainly about ______.

A.the beginnings of oceanography

B.the laying of the first undersea cable

C.the investigation of ocean depths

D.the early intercontinental communications

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    As high school students flock to social networking sites, campus police are scanningtheir Facebook and MySpace pages for tips to help break up fights, monitor gangs andprevent crime.
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    Some students object to police looking over their shoulders. But officers responsiblefor school safety say routine checks of the online forums often add to the knowledge theyobtain from hallways or schoolyards.
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    In recent years, school administrators have blamed some campus fights on Internetconflicts and urged parents to keep watch on their children's computer activity. But studentswho use the Web to let their 500 closest friends know what they are doing at all times aresometimes surprised that police are watching, too.
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    Police don't have special privileges on Facebook or MySpace. Students who want to gounobserved can change privacy settings so that their profiles are displayed only to a list ofapproved people. But the default (默认) settings leave those profiles open to many Internetusers (in the case of Facebook) or all of them (in the case of MySpace).
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    Employers and college admissions counselors have examined online profiles of studentapplicants for some time. Police across the country have been doing the same for the pasttwo or three years, said Kevin Quinn, a spokesman for the Minnesota-based National
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/Association of School Resource Officers.
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    "If you're already familiar with the technology, it doesn't take you but a couple ofminutes to hook into the student population and keep an eye on things," Quinn said.
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    An expedition into a thicket (丛林) of MySpace profiles found high school studentsdiscussing drugs, sex and fights. It was all publicly available (although in language thatcaused a reporter to blush).
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    Late last month, Fairfax County police announced the arrests of seven Chantilly areateenagers for trying to recruit Franklin Middle School students to a gang. That investigationwas aided when a student showed the school resource officer gang symbols littering one ofthe suspect's Myspace profiles.
style=color: rgb(51, 51, 51); font-family: "Microsoft YaHei"; white-space: normal; background-color: rgb(250, 250, 250);/    Fairfax police say they pride themselves on addressing issues in schools before theydevelop into major problems. Keeping an eye on Facebook and MySpace has become anextra tool in that effort, they said.

1.[单选题]Police officers scan social networking sites like Facebook or MySpace because ___________.

A.they have some special privileges to do so

B.they may detect gang-fighting through the Net

C.it is easier to solve students' conflicts online

D.it is their duty to protect students' privacy

2.[单选题]How did Fairfax County police identify the teenagers as gang members?

A.By investigating the students recruited.

B.By sending a policeman to spy on the gang.

C.By watching the spot they meet regularly.

D.By checking their self-descriptions online.

3.[单选题]What does "looking over their shoulders" (Line 1, Para.2) means in the passage?

A.Limit their time spending online.

B.Blame them for the conflicts.

C.Monitor what they said online.

D.Make schoolyard checking a routine.

4.[单选题]What does the author mainly discuss in the passage?

A.Students' neglect of protecting their privacy online.

B.Internet helping police maintain school and public order.

C.Social networking sites having bad influence on teenagers.

D.Police's unwelcome interference in students' online activities.

5.[单选题]Police can have access to many students' online profiles due to ___________.

A.students' casual attitude to private information

B.the technical support offered by the websites

C.the approval given by the students themselves

D.the special right granted by the governrnent

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