18．There was one thought that air pollution affected only the area immediately around large cities with factories and heavy traffic．At present．we realize that although these are the areas with the worst air．pollution．the problem is really worldwide．On several occasions over the past decade，a heavy cloud of air pollution has covered the east of the United States and brought health warnings in distant areas away from any industrial cities．In fact，the very climate of the entire earth may be infected by air pollution．Some scientists consider that the increasing concentration of carbon dioxide in the air resulting from the burning of fossil fuels（coal and oil）is creating a"greenhouse effect"一keeping heat reflected from the earth and raising the world's average temperature．If this view is correct and the world's temperature is raised only a few degrees．much of the polar ice cap will melt and．cities such as New York，Boston，Miami，and New Orleans will be in water．
Another view．1ess widely held．is that increasing particular matter in the atmosphere is blocking sunlight and lowering the earth's temperature-a result that would be equally disastrous．A drop of just a few degrees could create something close to a new ice age，and would make agriculture difficult or impossible in many of our top farming areas．Today we do not know for sure that either of these conditions will happen．Perhaps，if we are lucky enough，the two tendencies will offset each other and the world's temperature will stay about the same as it is now．Driven by economic profits．people ignore the damage on our environment caused by the"advanced civilization"．Maybe the air pollution is the price the human beings have to pay for their development．But is it really worth-while？

66．People used to think that air pollutionD．
A．caused widespread damage in the countryside
B．affected the entire eastern half of the United States
C．had a very bad effect on health
D．existed merely in urban and industrial areas
67．As to the greenhouse effect．the authorB．
A．shares the same view，with the scientists．
B．is uncertain of its occurrence
C．rejects it as being ungrounded
D．thinks that it will destroy the world soon
68．The underlined word"offset"in the second paragraph could be replaced byA．
A．counter-act    B．break from     C．get along    D．communicate
69．If the world's temperature lowered just a few degreesB．
A．it would not do much harm to life on earth
B．it would lead major farming areas to disaster
C．particular things would increase greatly in the atmosphere
D．seas and oceans would flood many cities
70．This passage is primarily aboutC．
A．the greenhouse effect                
B．the burning of fossil fuels
C．the potential effect of air pollution       
D．the possibility of a new ice age．

17．What will power your house in the future？According to scientists at the Massachusetts Institute of Technology （MIT） in the US，it might be artificial leaves．
Natural leaves can change sunlight and water into energy．It is known as photosynthesis（光合作用）．Now researchers have found a way to imitate this process．
The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts（催化剂）．Similar to natural leaves，it can split water into hydrogen and oxygen when put into a bucket of water．The hydrogen and oxygen gases are then stored in a fuel cell，using those two materials to produce electricity，located either on top of a house or beside the house．
Though the leaf is shaped like a poker card，scientists stated that it is promising to be an inexpensive somtoe of electricity in developing countries．"One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology，"said an American scientist，Docera．
An artificial leaf is not a new idea．The first artificial leaf was invented in 1997but too expensive and unstable for practical use．The new leaf，however，is made of cheap materials，easy to use and highly stable．In laboratory studies，Nocera showed that an artificial leaf could operate continuously for at least 45hours．
The wonderful improvements come from Nocera's recent discovery of several powerful new，inexpensive catalysts．These catalysts make the energy transformation inside the leaf more efficient with water and sunlight．Right now，the new leaf is about 10times more effective at carrying out photosynthesis than a natural one．Besides，the device can run in whatever water is available．
Hopefully，each home could possible have the access to the new application in the future．

71．The purpose of this article is toC．
A．promote the new product                   B．ask people to do the research
C．introduce a new kind of energy            D．show the process of photosynthesis
72．Which of the following is NOT the advantage of the new leaf？A
A．It has a wonderful fuel cell．
B．It is small in size．
C．It is low in cost．
D．It is convenient for people to use．
73．What conclusion can be drawn from the text？D
A．Docera thought the new leaf is expensive for developing countries．
B．Villages in Africa have benefited a lot from the new invention．
C．Silicon chip can help the new leaf work more effectively．
D．The equipment doesn't necessarily operate in pure water．
74．What's the writer's attitude towards the new device？B
A．Negative．  B．Optimistic．  C．Doubtful．  D．Uncertain．
75．According to the text，what will take place in the future？C
A．New leaves will take the place of natural leaves．
B．Scientists will develop more ways to produce energy．
C．The new invention could be widely used in the future．
D．Developing countries will contribute more to the research．

16．Suppose you don't need your car today．And suppose，as it happens，that a stranger in your area does need a car．Would you be willing to rent yours out？
Severalcar-sharing start-ups，including Getaround，RelayRides and JustShareIt，are eager to conneccar owners with renters this way．The companies have different rules，but participating owners receive，generally speaking，about two-thirds of the rental earnings．RelayRides says an owner of a midsize，late-model sedan who rents out a car for 10hours a week could expect to clear about＄3，000a year．
Peer-to-peer car sharing remains in the trial stage； it can be found in San Francisco and a few other places．It has a long way to go before it becomes the auto equivalent of Airbnb，the surprise success story for peer-to-peer sharing of space in apartments and houses．
Shelby Clark，founder of RelayRides，says potential investors in his company have been concerned that owners will be afraid to hand their car over to strangers．To address that，he points to Airbnb，saying，"Letting people sleep in your living room is much more of a disturbance into your personal space than letting someone use your car．"
All of these companies offer their own insurance coverage for their renters，which are supposed to put owners'minds at ease．But only two states-California and Oregon-have passed laws to clarify that an owner will not suffer any consequences should a car-sharing renter have an accident．
"In all the other states，legal ambiguity remains，"Shelby Clark says．"If a renter should be involved in a serious accident in those states，the victim can be expected to go after every party possible，including the car's owner．"
Also to remove the worries of car owners，the driving records of renters are checked for recent serious violations．

56．What does the underlined word"sedan"in Paragraph 2probably refer to？D
A．A kind of car．      B．An owner of a car．
C．A renting company．  D．A car-sharing renter．
57．Which of the following is true of Airbnb？A
A．It cares little about personal privacy．
B．It deals with house-sharing successfully．
C．It is a very popular car-sharing company．
D．Its ideas are being tried out in some states．
58．If a car-sharing renter should have an accident in California，the car's ownerB．
A．has to take legal responsibility
B．will not suffer the consequence
C．is not covered by health insurance
D．must pay the insurance for the renter
59．According to the text，more car-owners will participate in the service，ifA
A．legal ambiguity is clarified in all the states
B．renters are warned not to violate traffic rules
C．more money is given to participating owners
D．people are aware of the importance of sharing
60．It can be learned from the text that car-sharingD
A．makes no profit
B．remains in popularity
C．is against the state law 
D．is a new business model．

15．One couple spent a holiday driving in the mountains．"Every time you race around one of those narrow curves （弯道），"screamed the wife，"I just get（36）B．"
"Then do what I do，"（37）Aher husband．"Close your eyes!"
We are all afraid at times，but closing our eyes is not always a（38）Dway through fear．Better to（39）Cyour eyes and face those fears head-on．
In 1972David Smith had such a（n）（40）D．Smith，an adventurer，decided to spend a night （410）Ain St．Michael's Cave as a test of（42）C．In his book HUG THE MONSTER （魔鬼），he tells of hearing（43）Bsounds all around him as he lay there in the dark，damp，and deserted cave．Most frightening was the fact that he came to believe he was（44）Calone!
Fear became panic and he was afraid he was losing his mind．Then suddenly，（45）D he was approaching his psychological（46）B point．Smith thought to himself，"Whatever the monster looks like，I will（47）Ait．"That simple，almost silly thought brought great（48）Cto his restless mind．He soon fell into a（49）Band peaceful sleep until morning．He learned that hugging his fear（50）Dhim to overcome it．
We each have our nights of fear．We each come across monsters of some sort．We（51）Afear insects，heights，crowds or death．And we are sometimes visited by（52）Aof these monsters in the dark of night．
The next time you're afraid，（53）B"hugging the monster．"You may be surprised at how quickly it （54）Cand at how confident you begin to feel．Like that beautiful spirit Eleanor Roosevelt said，"You gain strength，courage，and confidence by every（55）Din which you stop to look fear in the face．"
Do you have a monster to hug？

36．A．disappointed	B．frightened	C．excited	D．interested
37．A．suggested	B．ordered	C．scolded	D．declared
38．A．dangerous	B．harmful	C．healthy	D．helpful
39．A．cover	B．roll	C．open	D．close
40．A．journey	B．dream	C．accident	D．opportunity
41．A．alone	B．altogether	C．abroad	D．anywhere
42．A．strength	B．skill	C．courage	D．wisdom
43．A．familiar	B．strange	C．appealing	D．desperate
44．A．just	B．almost	C．not	D．still
45．A．because	B．though	C．after	D．as
46．A．freezing	B．breaking	C．burning	D．turning
47．A．hug	B．kill	C．ignore	D．admire
48．A．anxiety	B．delight	C．relief	D．fear
49．A．short	B．deep	C．shallow	D．permanent
50．A．convinced	B．attracted	C．forced	D．allowed
51．A．may	B．must	C．should	D．need
52．A．shadows	B．shades	C．voices	D．smiles
53．A．risk	B．try	C．forget	D．avoid
54．A．takes off	B．turns up	C．slips away	D．breaks in
55．A．contribution	B．competition	C．experiment	D．experience

14．Although new laws have been passed in some American states to cut down on Distracted（分心的） driving，many accidents and deaths were still related with it，especially using cell phones while driving．Recently the Obama administration is considering disabling cell phones in cars aiming to cut down cell-phone-related road deaths．
Transportation Secretary Ray LaHood，the nation's anti-distracted-driving supporter，said in an interview on November 18that federal officials are looking at technology to disable cell phones inside cars．
"I think it will be done，"LaHood said．"I think the technology is there and I think you're going to see the technology become adaptable in automobiles to disable these cell phones-We need to do a lot more if we were going to save lives．"
Also on Thursday，the transportation government started a new"Faces of Distracted Driving"video campaign that features people who have been killed or lost their loved ones because of inattentive drivers．The video features heartbreaking stories of children killed，in crashes because of phoning or text messaging，and new videos are expected to be added every few weeks．
A driver is four times more likely to crash while using a mobile phone．More than 5，500people were killed last year by distracted drivers，and another 500，000were injured．LaHood has said it is never safe to talk on a cell phone while driving，hands-free or not，because it can really cause distraction．
Incidentally，a lot of people seem to agree with this viewpoint-a new research shows nearly two-thirds of Americans support a national ban on the use of cell phones while driving，even if the driver is using a hands-free device（装置）．But the research didn't ask how people feel about government-issued  mobile phone scramblers or other disabling devices．

63．We can learn from the text that Ray LaHoodB．
A．is in charge of the invention of the technology
B．is strongly for the use of the technology in cars
C．thinks it's easy and practical to invent the technology
D．thinks it's unnecessary to use cell phone while driving
64．The"Faces of Distracted Driving"video campaign aims toC．
A．find out the real drivers who caused the accidents
B．show that most of the victims in car crashes are children
C．make the public aware of the terrible results of distracted driving
D．call on drivers to buy the new device which disables cell phones in cars
65．In the last paragraph，the"mobile phone scramblers"are probablyA．
A．a kind of disabling devices
B．a kind of hands-free devices
C．a new kind of cell phones
D．new devices to help text messaging
66．We can infer from me text thatD．
A．most people realize the harmfulness of distracted driving
B．the disabling devices in cars will be widely used if it is free
C．most people would like to choose hands-free devices while driving
D．the writer is not sure whether disabling devices will be accepted by the drivers．

13．"Get your hands off  me，I have been stolen，"the laptop，a portable computer，shouted．That is a new solution to laptop computer theft：a program that lets owners give their property a voice when it has been taken．
     The Program allows users to display alerts （警觉） on the missing computer's screen and even to set a spoken message．Tracking software for stolen laptops has been on the market for some time，but this is thought to be the first that allows owners to give the thief a piece of their mind．
     Owners must report their laptop missing by visiting a website，which sends a message to the model：a red and yellow"lost or stolen"sign appears on its screen when it is started．Under the latest version （版本） of the software，users can also send a spoken message．
   The message can be set to reappear every 30 seconds，no matter how many times the thief closes it．"One customer sent a message saying，'You are being tracked．I am right at your door．"said Carrie Hafeman，chief executive of the company which produces the program，Retriever．
In the latest version，people can add a spoken message．For example，the laptop's speakers will say，"Help，this laptop is reported lost or stolen．If you are not my owner，report me now．"
The Retriever software package，which costs $29.95 but has a free trial period，has the functions of many  security  software  programs．Owners can remotely switch to an alternative password if they fear that the thief has also got hold of the access details．
     If a thief accesses the internet with the stolen laptop，Retriever will collect information on the internet service provider in use，So that the police can be alerted to its location；
    Thousands of laptops are stolen every year from homes and offices，but with the use of laptops increasing，the number stolen while their owners are out and about has been rising sharply．
     Other security software allows users to erase data remotely or lock down the computer．

36．The expression"to give the thief a piece of their mind"（Para.2）means"B"
     A．to give the thief an alert mind
     B．to express the owners'anger to the thief
     C．to remind the thief of this conscience
     D，to make the thief give up his mind
37．Different from other security software，Retriever canD   
     A．record the stealing process
     B．help recognize the lost laptop
     C．lock down the computer remotely
     D．send a spoken message
38．One function of the program is that it allows the owner toAat a distance，
     A．change some access details for switching on the laptop
     B．turn on the laptop by using the original password
     C．operate the laptop by means of an alternative password
     D．erase the information kept in the stolen laptop
39．Which of the following can best summarize the main idea of the passage？B
     A．With no Retriever，thousands of laptops are stolen every year．
     B．A new software provides a means to reduce laptop theft．
     C．Retriever has helped to find thieves and lost computers．
     D．A new program offers a communication platform with the thief．
40．What is the author's attitude towards the programme？C
     A．Doubtful．    B．Acceptable．
     C，Positive．    D．Negative．

12．Recently，Pew Research Center announced that over a quarter of Americans have shared a selfie online．Unsurprisingly，the practice of photographing oneself and sharing that image via social media has （51）A among all age groups．Evidence of its mainstream nature is seen in other aspects of our culture too．Last year，"selfie"was not only added to the Oxford English Dictionary，but also named Word of the Year．
Yet，despite the huge number of people practicing it，（52）B is also surrounding selfie．An assumption that sharing selfies is embarrassing runs throughout the journalistic and scholarly coverage on the topic．Negative words like"self-centered"and"（53）C"have inevitably become a part of any conversation about selfies among scholars．
But，over a quarter of all Americans are relying on it．Why？The usual reasons given by scholars-self-center and fame-seeking-seem too （54）D to explain such a crowd acting．There is always more to a social cultural practice than what （55）A．
Simply put，physical and digital technology make it possible．The idea that technology （56）C the social world and our lives has been recognized by people．To some extent，world is shaped by technological revolutions．The selfie is not a（n） （57）B form of expression．Artists have created self-portraits for centuries，from cave to oil paintings，to early photography and modern art．People are （58）D their feelings and thoughts through certain media．What's original about today's selfie is its public popularity．Technological advancement （59）A the self-portrait used to be restricted to the art world and gave it to the masses．Those digital front-facing cameras，social media platforms，and wireless communications conveniently available  make selfie a job （60）B any time anywhere．
Besides，We are not （61）A beings living by ourselves．We are social beings who live in social communities，and as such，our lives are fundamentally formed by social relations with other people．As photos meant to be （62）B，selfies are not individual acts； they are social gestures．Selfies，as well as our presence on social media generally，are a part of"identity work"--the work that we do on a daily basis to （63）C that we are seen by others as we wish to be seen．In fact，the crafting and display of identity has long been understood as a social process．The selfies we take and show are to present a （64）D image of us so as to become a part of our identity formation and（65）D．

51．A．flowered	B．returned	C．imposed	D．functioned
52．A．negotiation	B．criticism	C．regret	D．punishment
53．A．self-contained	B．self-evident	C．self-absorbed	D．self-financed
54．A．necessary	B．smart	C．certain	D．shallow
55．A．meets the eye	B．takes the lead	C．raises the alarm	D．makes the point
56．A．operates	B．produces	C．structures	D．ruins
57．A．advanced	B．new	C．intelligent	D．available
58．A．offering	B．revising	C．inspiring	D．conveying
59．A．liberated	B．tagged	C．honoured	D．maintained
60．A．at length	B．with ease	C．at large	D．with regards
61．A．isolated	B．courageous	C．traditional	D．civilized
62．A．saved	B．shared	C．updated	D．deleted
63．A．claim	B．suppose	C．ensure	D．signal
64．A．fashionable	B．skillful	C．mysterious	D．particular
65．A．summary	B．evaluation	C．monitoring	D．exhibition

11．A new study suggests that early exposure to germs（细菌） strengthens the immune（免疫的）system．That means letting children get a little dirty might be good for their health later in life．
The study involved laboratory mice．It found that adult mice raised in a germ-free environment were more likely to develop allergies．asthma and other autoimmune disorders． There are more than eighty disorders where cells that normally defend the body instead attack tissues and organs．
Richard Blumberg，who led the study，is a professor at'Harvard Medical School in Boston，Massachusetts．He says，in 1989，medical researchers who sought to explain these diseases，first discovered that the increasing use of antibacterial soaps and other products，especially early in life，could weaken immune systems．
Now，Dr．Blumberg and his team have what is the first biological evidence to link early exposure to germs to stronger adult immune systems．They say this exposure could prevent the development of some autoimmune diseases．
In the adult germ-free mice，they found that inflammation（发炎）in the lungs and colon was caused by so-called killer T cells．These normally fight infection．But they became overactive and targeted healthy tissue-an autoimmune condition seen in asthma and a disease called ulcerative colitis．
Dr，Blumberg says the mice raised in a normal environment did not have the same reaction．He says their immune systems had been"educated"by early exposure to germs．
Rates of autoimmune disorders are rising worldwide，but mostly in wealthier，industrialized countries．According to Dr．Blumberg，it might be high time that people were warned to be more careful with the early use of antibiotics（抗生素） and the prescription from their doctors．
Rob Dunn is a professor of ecology and evolutionary biology at North Carolina State University in Raleigh．He says the new study does not mean people should stop washing．"Wash your hands，but don't do it with antibacterial soap．Let your kids play in a reasonable amount of dirt and get outside and get exposed to a diversity of things"，says Rob Dunn．
71．Who first found immune systems might get harmed by overly using antibacterial products？C
A．A professor of ecology and evolutionary biology．
B．A professor at Harvard Medical School in Boston．
C．Medical researchers who tried to explain autoimmune disorders．
D．Medical researchers who tried to treat autoimmune disorders．
72．To keep healthy in the future，children had betterA．
A．play in a dirty environment once in a while
B．live in a germ-free endronrnent
C．use plenty of antibacterial soaps
D．stay in under developed countries
73．Why are germ-free mice easy to develop lung inflanunation？B
A．Because their T celh fight bacteria effectively．
B．Because their T cells attack the healthy tissues．
C．Because their lungs become abnormally active．
D．Because their lungs have weaker tissues．
74．It can be inferred from the text thatD．
A．washing hands is no longer a good habit for children
B．antibiotics will be forbidden in children's hospitals
C．exposure to dirt helps build children's character
D．the abuse of antibiotics may be condemned
75．Where does this text most probably come from？C
A．A teacher's handbook．     B．A story book．
C．A science magazine．       D．A travel journal．

10．Mass Migration
Mass Migration  Look up at the sky one autumn day and you might see a flock of birds in V-formation．（71）DAll summer，they have lived in the north where they made their nests，laid their eggs，hatched，and raised their young．Soon，snow and ice will cover all their northern breeding grounds，so they must migrate south where food is easier to find．It is necessary to create worldwide bird sanctuaries（保护区） before many of these species become extinct（灭绝）．
（72）C  The Arctic tern travels 10，625miles from one polar region to the other．This may be the longest migration of any animal on Earth．Not all birds migrate．Some are able to adapt to winter by changing their diets．（73）A  For most species，however，it is easier to migrate to climates that are not as severe．
Somehow，migrating birds know exactly where they are going and how to get there．It is amazing to think about how birds are able to return to the same place year after year．（74）F Other scientists believe that migratory birds navigate by following certain coastlines，mountains，and rivers．However they do it，these amazing creatures always arrive in the right place at the right time．In the spring，they return to their nesting grounds up north to lay their eggs and care for their young．
It is important for the people of the world to protect the estuaries （河口）and wetlands．（75）B  With so many species of birds'habitats threatened worldwide，our children may never be able to enjoy the beauty of these migrating wonders．

A．These birds stay in the same place all year．
B．They are important to endangered species．
C．Some birds travel great distances，crossing entire continents and oceans．
D．They are flying south where there is warmth and food during the winter．
E．Birds fly around the world according to the weather year around year．
F．Some scientists think it is possible for birds to use the stars to find their way．
G．The birds that migrate south in winter return to different places when weather is warm．

9．Nearly all of us have dreamed about winning the big prize in a lottery（彩票）．We dream about （16）what we would do with the money，but we rarely stop to think about how the money would change us．
For most of us，our way of life is closely linked （17）to/with 0ur economic circumstances．The
different parts of  （18）our lives fit together like a jigsaw（拼板）-work，home，friends，hobbies，and sports make up our world．（19）A sudden fortune would change it all and break the jigsaw．For example，most people like the idea （20）of not having to work，but winners have found that without work there is no reason to get up in the morning．It seems great  （21）to move  （move） to a bigger house in a wealthy area，（22）but if you do that，you leave old friends behind．
Usually，winners （23）are advised （advise） not to publicize their address and phone number，but begging letters still arrive．（24）If they are not careful，most of their money will be spent on the （25）protection （protect） of their homes and swimming pools and their sanity!