SometimesIreallydoubtwhetherth-优题课

Cutting meat production and consumption by 30 percent would help to reduce carbon emissions(排放) and improve health in the most meat-loving nations, scientists said on Wednesday.
Using prediction models, British and Australian researchers1 that improving efficiency, increasing carbon capture and2 fossil fuel dependence in farming would not be enough to3 emissions targets.
But combining these steps4 a 30 percent reduction in livestock（家畜） 5 in major meat-producing nations and a similar6 in meat-eating, would lead to "substantial population health benefits" and cut emissions, they said.
The study found that in Britain, a 30 percent7 intake of animal-source saturated（饱和的） fat by adults would reduce the8 of premature（过早的） deaths from heart disease by some 17 percent -- equivalent to 18,000 premature deaths reduced in one year.
In Sao Paulo, Brazil, it could mean as9 as 1,000 premature deaths reduced in a year, they said.
10 the United Nations Food and Agricultural Organization, 18 percent of all greenhouse gas emissions are from meat production and experts say rising11 for meat, particularly in countries with growing economies, could12 livestock production up by 85 percent from 2000 levels13 2030.
The scientists said global action was needed to maximize the benefits of cutting meat production and14 , and that the environmental15 "may apply only in those countries that currently have high production levels."
The study was16 in The Lancet medical journal as part of a series in climate change and health17 the Copenhagen global climate summit scheduled next month.
In a second study, British scientists found that increased walking and cycling, and18 cars, would have a much greater impact on health19 low-emission vehicles in rich and middle-income countries.
Andrew Haines, director of the London School of Hygiene and Tropical Medicine and head of the research series, said delegates at Copenhagen needed "to understand the potential20 impacts of their plans."
( ) 1. A. invented B. experimented C. found D. proved
( ) 2. A. increasing B. speeding C. stopping D. reducing
( ) 3. A. meet B. change C. break D. adapt
( ) 4. A. by B. with C. to D. in
( ) 5. A. sale B. eating C. production D. use
( ) 6. A. cut B. increase C. addition D. consumption
( ) 7. A. lower B. higher C. more D. less
( ) 8. A. amount B. number C. quantity D. deal
( ) 9. A. much B. many C. few D. little
( ) 10. A. According to B. Apart from C. As well as D. In addition to
( ) 11. A. resistance B. fear C. demand D. anxiety
( ) 12. A. weaken B. strengthen C. drive D. broaden
( ) 13. A. in B. by C. from D. after
( ) 14. A. evaluation B. consumption C. process D. store
( ) 15. A. advantage B. disadvantage C. pollution D. improvement
( ) 16. A. written B. claimed C. delivered D. published
( ) 17. A. along with B. from behind C. ahead of D. in front of
( ) 18. A. more B. fewer C. no . none
( ) 19. A. then B. as C. that D. than
( ) 20. A. health B. body C. spirit D. emotion

Are you a social butterfly, or do you prefer being at the edge of a group of friends? Either way, your genes and evolution may play a major 1 , US researchers reported on Monday.
While it may come as no surprise that genes may help explain 2 some people have many friends and others have 3 , the researchers said, their findings go just a little farther than that.
"Some of the things we find are 4 uncommon," said Nicholas Christakis of Harvard University in Massachusetts, who helped 5 the study.
"We find that how interconnected your friends are 6 on your genes. Some people have four friends who know each other and some people have four friends who don't 7 each other. 8Dick and Harry know each other depends on Tom's 9 ," Christakis said in a telephone interview.
Christakis and colleague James Fowler of the University of California San Diego are 10 known for their studies that show obesity, smoking and happiness spread in networks.
For this study, they and Christopher Dawes of UCSD used national data that 11 more than 1,000 identical(同卵的) and fraternal（异卵的） twins’ genes. Because 12 share an environment, these studies are good for showing the impact that genes have 13 various things, because identical twins 14 all their genes while fraternal twins share just half.
"We found there appears to be a genetic tendency to introduce your friends 15 each other," Christakis said.
There could be good, evolutionary reasons 16 this. People in the middle of a social network could be secret to useful gossip, 17 the location of food or good investment choices.
But they would also be at risk of catching effects from all sides -- in which case the advantage would 18 more cautious social behavior, they wrote in the Proceedings of the National Academy of Sciences.
"It may be that natural selection is19 not just things like whether or not we can resist the common cold, but also who it is that we are going to come into 20 with," Fowler said in a statement.
( ) 1. A. role B. rule C. roll D. pole
( ) 2. A. where B. why C. when D. how
( ) 3. A. a few B. several C. few D. some
( ) 4. A. generally B. mainly C. mostly D. frankly
( ) 5. A. conduct B. introduce C. conflict D. instruct
( ) 6. A. depends B. bases C. take D. put
( ) 7. A. see B. inspect C. learn D. know
( ) 8. A. When B. Where C. What D. Whether
( ) 9. A. genes B. brains C. appearances D. figures
( ) 10. A. much B. best C. very D. least
( ) 11. A. recorded B. illustrated C. described D. compared
( ) 12. A. brothers B. sisters C. twins D. cousins
( ) 13. A. with B. on C. for D. to
( ) 14. A. share B. have C. own D. show
( ) 15. A. into B. to C. in D. from
( ) 16. A. for B. with C. to D. at
( ) 17. A. in addition to B. due to C. as for D. such as
( ) 18. A. lie on B. bring in C. lie in D. send in
( ) 19. A. acting on B. putting on C. relying on D. sending on
( ) 20. A. contract B. face C. join D. contact

For those who are conditioned to think that learning only happens in a classroom, the world of self-learning can be a little daunting. How do we best take 1of these new opportunities?
Your interest in the subject is the essential driver of success. You can’t learn what you do not want to learn. Emotion is an important part of the learning 2. If you are even moderately interested in a subject, give yourself a chance. The key is to get started. If you can create some pleasurable 3 , you may find that the subject grows on you.
Don’t expect to understand things, much less remember them, the first time you study them. Trust that things will get clearer 4your brain comes to grips with new information. It is like a cross-word puzzle. As you start to put the pieces together, or string the words together, the full picture becomes clearer. The brain learns all the time, but 5 its own schedule. Learning does not take place according to a schedule laid down by a curriculum or teacher. Some things are easier to learn than others. Some things just take 6 to click in. Keep at it, and you will gradually find that things that seem difficult at first , will become easy with time.
Your brain is struggling to form patterns to 7new input from your learning activities. Sometimes, no matter how long you focus on one subject, your brain is not going to pick it up. If you are stuck, move 8 . Then cover the same general information from a different source, a different book, or a podcast, or an online lecture or a video. Try to become a grazing learner, roaming the countryside, 9a feedlot learner, just standing there in one spot. The broader your base, the easier it is to learn. Just as the “rich get richer”, the more you know, 10 you can learn.
Take full advantage of the Internet, iTunes, and 11mobile devices, not to mention good old-fashioned books and magazines. Learn during “dead time”. Listen in your car, on the train, or 12 jogging. Have your learning with you while waiting in the doctor’s office, or listen while checking out at the supermarket. Anytime is 13 time. Remember, you are learning through exposure, not by nailing things down. It is more like moisture accumulation in a 14, rather than building a brick wall.
The more varied your learning content, and the more varied the ways in which you learn, the 15 the puzzle will become. Different learning activities suit different people, at different times of the day. Vary your activities in order to keep your interest level 16 . Even if listening and reading work best for you, treat yourself to the odd video lecture, or get-together with other learners. This will renew your batteries.
The “loneliness of the distance learner” is a thing of the 17. Join a learning community on the web, where members share their knowledge and experience. Search for the communities that suit your interests and learning style. You will find encouragement, advice and stimulus from fellow learners, 18 from tutors, teachers and coaches. In these communities, you can measure your progress against your own goals, or compare your experience 19that of other learners. You can even teach and help others, which is a great way to learn.
Never has it been easier nor more exciting to be a learner. Let constant learning be a major part of your life-style. The 20will be constant, personally, socially, and professionally.
( ) 1. A. advantage B. place C. possession D. example
( ) 2. A. progress B. process C. pressure D. proposal
( ) 3. A. roads B. streets C. routines D. building
( ) 4. A. with B. if C. unless D. as
( ) 5. A. on B. to C. with D. for
( ) 6. A. shorter B. sooner C. longer D. lower
( ) 7. A. take with B. com with C. go with D. cope with
( ) 8. A. down B. on C. away D. off
( ) 9. A. more than B. less than C. rather than D. other than
( ) 10. A. less B. quicker C. lower D. more
( ) 11. A. same B. similar C. familiar D. various
( ) 12. A. while B. before C. after D. if
( ) 13. A. playing B. learning C. talking D. speaking
( ) 14. A. cloud B. sky C. earth D. sea
( ) 15. A. cleaner B. clearer C. harder D. lower
( ) 16. A. down B. up C. in D. out
( ) 17. A. present B. day C. past D. night
( ) 18. A. as long as B. as far as C. as well as D. as soon as
( ) 19. A. without B. with C. to D. beyond
( ) 20. A. awards B. words C. remarks D. rewards

Fifteen percent of US teenagers aged 12 to 17 who own mobile phones have received nude（裸体）or nearly nude images of someone they know, according to a survey released on Tuesday.
Only four percent of mobile phone-owning 1 in that age group have sent sexually suggestive pictures of themselves, a practice known as "sexting," 2 the Pew Research Center’s Internet & American Life Project.
The Pew survey found that girls and boys were equally as likely to have sent a suggestive picture to 3 person and 4 teenagers were more likely to have engaged in "sexting."
Eight percent of 17-year-olds with mobile phones have sent a sexually provocative（刺激的） image 5 texting and 30 percent have 6 a nude or nearly nude image on their phone.
Only four percent of 12-year-olds have sent suggestive images of 7 .
Amanda Lenhart, a senior research specialist at Pew and the author of the report, said sexually suggestive images have become a 8 of "relationship currency" for teens.
"These images are 9 as a part of or instead of sexual activity, or as a way of starting or 10 a relationship with a significant other," she said. "And they are also passed 11 to friends for their entertainment value, as a joke or for 12 ."
"The desire for risk-taking and sexual exploration during the teenage years 13 with a constant connection via mobile devices creates a 'perfect storm' for sexting," said Lenhart.
"Teenagers have always grappled with issues around sex and 14 , but their coming-of-age mistakes transgressions have never been so easily 15 and stored for others to see," she added.
The survey found that teens with unlimited text messaging plans were more likely to receive "sexts" 16 images of people they know. About 75 percent of mobile phone owning teens have unlimited plans.
Among this group, Pew said 18 percent reporting receiving "sexts" 17 with eight percent of teens on 18 data plans and three percent of teens who pay per message.
According to Pew, 58 percent of 12-year-olds own a mobile phone and 83 percent teens aged 17 19 .
Pew noted that a number of US states are grappling with how to 20 "sexting" among minors and some legislatures(立法机关) have stepped in to consider laws that would downgrade charges from felonies（重罪） to misdemeanors（轻罪）.
Pew conducted telephone interviews with 800 teens aged 12 to 17 and their parents between June 26 and September 24.
( ) 1. A. teens B. adults C. students D. parents
( ) 2. A. referring to B. reporting C. saying D. according to
( ) 3. A. other B. another C. others D. the other
( ) 4. A. younger B. fewer C. older D. more
( ) 5. A. by B. in C. on D. through
( ) 6. A. accepted B. received C. sent D. mailed
( ) 7. A. others B. themselves C. himself D. herself
( ) 8. A. habit B. system C. method D. form
( ) 9. A. shared B. limited C. tasted D. controlled
( ) 10. A. remaining B. gaining C. maintaining D. obtain
( ) 11. A. along B. by C. as D. for
( ) 12. A. joy B. fun C. excitement D. delight
( ) 13. A. compared B. followed C. combined D. went
( ) 14. A. friendships B. scholarships C. relatives D. relationships
( ) 15. A. transmitted B. transformed C. formed D. switched
( ) 16. A. containing B. concluding C. including D. concerning
( ) 17. A. comparing B. compared C. connected D. joined
( ) 18. A. limited B. unlimited C. few D. little
( ) 19. A. have B. same C. do D. too
( ) 20. A. do with B. deal with C. remove D. ban

Elderly people who drink several cups of green tea a day are less likely to suffer from depression, probably due to a "feel good" chemical found in this type of tea, Japanese researchers said.
Several studies have 1 drinking green tea to lessening psychological problems and Kaijun Niu, of Tohoku University Graduate School, and colleagues found people 2 70 and older who drank four or more cups of green tea daily were 44 percent 3 likely to experience depression.
Green tea is widely 4 in many Asian countries, 5 China and Japan.
Niu's team 6 1,058 relatively healthy elderly men and women. About 34 percent of the men and 39 percent of the women had symptoms of 7 , according to the study that was 8 in the American Journal of Clinical Nutrition.
A total of 488 participants said they 9 four or more cups of green tea a day, 284 said they downed two to three cups 10 and the rest reported having one or fewer cups daily.
According to the researchers, the 11 effect of drinking more 12 tea on alleviating symptoms of depression did not 13 after they factored in social and economic status, gender, diet, history of medical problems and 14 of antidepressants.
There was no15 between consumption of black or oolong tea, or coffee, and 16 symptoms of depression.
A green tea component, the amino acid thiamine（硫胺素）, which is 17 to have a tranquilizing（镇静的） 18 on the brain, may 19 the "potentially beneficial effect" shown in the current study, Niu noted, 20 that more study is needed.
( ) 1. A. linked B. taken C. considered D. regarded
( ) 2. A. aging B. aged C. years D. age
( ) 3. A. more B. little C. less D. much
( ) 4. A. sold B. planted C. spread D. consumed
( ) 5. A. including B. concluding C. containing D. considering
( ) 6. A. looked for B. checked C. investigated D. asked
( ) 7. A. optimism B. happiness C. bitterness D. depression
( ) 8. A. published B. come out C. appeared D. showed
( ) 9. A. ate B. drank C. swallowed D. chewed
( ) 10. A. weekly B. daily C. monthly D. yearly
( ) 11. A. apparent B. light C. huge D. gentle
( ) 12. A. black B. oolong C. coffee D. green
( ) 13. A. fade B. disappear C. run D. decease
( ) 14. A. influence B. effect C. use D. result
( ) 15. A. association B. use C. comparison D. difference
( ) 16. A. lower B. increase C. strengthen D. cause
( ) 17. A. assumed B. thought C. imaged D. hoped
( ) 18. A. effect B. affect C. effort D. outcome
( ) 19. A. report B. confirm C. complete D. explain
( ) 20. A. adding B. addressing C. speaking D. saying