Suppose you become a leader in an organization. It’s very likely that you’ll want to have volunteers to help with the organization’s activities.To do so,it should help to understand why people undertake volunteer work and what keeps their interest in the work.

Let’s begin with the question of why people volunteer.Researchers have identified several factors that motivate people to get involved.For example,people volunteer to express personal values related to unselfishness,to expand their range of experiences,and to strengthen social relationships.If volunteer positions do not meet these needs,people may not wish to participate.To select volunteers,you may need to understand the motivations of the people you wish to attract.

People also volunteer because they are required to do so.To increase levels of community service,some schools have launched compulsory volunteer programs.Unfortunately,these programs can shift people’s wish of participation from an internal factor(e.g.,“I volunteer because it’s important to me”)to an external factor(e.g.,“I volunteer because I’m required to do so”).When that happens,people become less likely to volunteer in the future.People must be sensitive to this possibility when they make volunteer activities a must.

Once people begin to volunteer,what leads them to remain in their positions over time?To answer this question,researchers have conducted follow-up studies in which they track volunteers over time.For instance,one study followed 238 volunteers in Florida over a year.One of the most important factors that influenced their satisfaction as volunteers was the amount of suffering they experienced in their volunteer positions.Although this result may not surprise you,it leads to important practical advice.The researchers note that attention should be given to“training methods that would prepare volunteers for troublesome situations or provide them with strategies for coping with the problem they do experience”.

Another study of 302 volunteers at hospitals in Chicago focused on individual differences in the degree to which people view“volunteer”as an important social role.It was assumed that those people for whom the role of volunteer was most part of their personal identity would also be most likely to continue volunteer work.Participants indicated the degree to which the social role mattered by responding to statements such as“Volunteering in Hospital is an important part of who I am.”Consistent with the researchers’ expectations,they found a positive correlation(正相关)between the strength of role identity and the length of time people continued to volunteer.These results,once again,lead to concrete advice:“Once an individual begins volunteering,continued efforts might focus on developing a volunteer role identity... Items like T-shirts that allow volunteers to be recognized publicly for their contributions can help strengthen role identity”.

The year 2114 will be an eventful one for art. In May of that year in Berlin, the philosopher-artist Jonathon Keats’ “century cameras” – cameras with a 100-year-long exposure (曝光）time – will be brought back from hiding places around the city to have their results developed and exhibited. Six months after that, the Future Library in Oslo, Norway, will open its doors for the first time, presenting 100 books printed on the wood of trees planted in the distant past of 2014.

As Katie Paterson, the creator of the Future Library, puts it: “Future Library is an artwork for future generations.” These projects, more than a century in the making, are part of a new wave of “slow art” intended to push viewers and participants to think beyond their own lifetimes. They aim to challenge today’s short-term thinking and the brief attention spans of modern consumers, forcing people into considering works more deliberately. In their way, too, they are fighting against modern culture – not just regarding money, but also the way in which artistic worth is measured by attention.

In a similar fashion, every April on Slow Art Day, visitors are encouraged to stare at five works of art for 10 minutes at a time – a tough task for the average museum visitor, who typically spends less than 30 seconds on each piece of art.

Like the Future Library, the century cameras are very much a project for cities, since it’s in cities that time runs fastest and the pace of life is fastest. “Since I started living in a city, I’ve somehow been quite disconnected,” Anne Beate Hovind, the Future Library project manager, who described how working on the library drew her back to the pace of life she knew when she was growing up on a farm in her youth, told The Atlantic magazine.

 I have always considered myself a positive thinker, an upbeat person and an optimist. I try to find the best in every situation. I’ve recently become aware of how two little words in my vocabulary have had a tremendous impact on people. I didn’t even realize it. 

  I’ve been listening to myself lately, and I don’t like the way I sound. As a veteran (资深的)teacher, I know that praise can be a huge motivational tool. I realize the importance of developing a child’s self-esteem. I generously sprinkle(洒) uplifting comments around my classroom like I am fertilizing flowers. Each new school year brings a garden variety of students, and they all blossom (开花)with praise and encouragement. I know how to thank my grown kids, my grandkids and my husband for a job well done. I toss praise to the unsuspecting if it appears someone needs a lift. I also yo-yo my positive comments right back when I use the word that makes my preschoolers giggle-BUT.    

When one of my students attempted to print her name, I oohed and ahhed. “Wow! That is a great A, and your letter, D is nice and tall, but your letter, E should be short; can you erase it and try to make it shorter?” I asked. She wasn’t crushed by my comment. She tried to live up to my expectation. I thought I was helping, preparing her for kindergarten, showing her the difference in size between upper case and lower case letters. I don’t believe that my comment would have any long term affect on her self-worth. I imagine though, if I’d substituted the word BUT with the word AND, she’d have been proud of her accomplishment instead of questioning the “right way” to print her name. I wish I had said, “I like your nice tall letters, AND I like how hard you are trying to make your letter E.”

My recently divorced daughter called to tell me about a house she was interested in. I listened to her. I applauded her for moving forward with her life, and I said, “Honey, I am glad that you’ve found something you like, but…” There, I did it again!” Don’t you think, with the gas prices, you might want to buy closer to your work?” As she told me all about the prospective house, I could hear the excitement and joy in her voice. The moment I spoke the word, BUT, it was as if I pricked (刺)a balloon with a needle. I could hear her slowly deflate. I sure wish I’d used the word AND. “Honey, I’m glad you found a house in your price range, AND I’m happy for you.” She knows I freely express my opinions, and I know she’s used to my mouth. I suspect that if I had leashed(管住) my tongue, her emotions wouldn’t have flip-flopped, and we’d have both hung up feeling better.

My dear husband helps around the house; he did the dishes, emptied the dishwasher, and folded the laundry. I was thrilled he had lightened my work load. I thanked him. I told him how wonderful he is, and I used that naughty word again. “BUT, why did you leave small pieces of bread all over the counter?” Why? Why? Why didn’t I say, “Thank you, AND I appreciate all you do around the house.”

I’ve been doing some self-reflecting. I’ve given up on losing those twenty pounds. I’ve decided a walk around the neighborhood is a good substitute for vigorous exercise. I’ve watched dust bunnies pile up under the sofa. I’ve prayed in the dark instead of at church more often than not. In other words, all those New Year’s resolutions (决心；决定)are now null and void. I lose a pound; I eat a chocolate; I gain a pound. The bar on my treadmill(跑步机) makes a nice rack for hanging laundry. I’ve attended church for grand children’s christenings, and I pass the sanctuary(圣殿) on my way to the church office. I vacuum on weekends. I figure if the dust bunnies don’t mind snuggling(躺着) for another day, I don’t care either.

My house isn’t spotless, my thighs are heavy, my soul, like my face could use some uplifting, but I have decided that I simply cannot keep all those resolutions I made on January 1st. I’m ready for some spring cleaning. I’m tossing those old resolutions out and I am making one, just one, which I intend to keep. I am going to refrain (忍住)from using the B word. I think I can do it, and I am going to give it my best. I know it will have a positive effect on others. BUT if I mess up, I will try again, and again, and again to remove that naughty little word from my vocabulary. I resolve to replace it with the word AND. This is a resolution I intend to keep!

In 2013 alone at least 20,000 African elephants were killed for their teeth. In South Africa over the last two years more than 2,200 rhinos were killed for their horns. These numbers are alarming, because current rates of illegal hunting are faster than birth rates, which could lead to extinction for these ecologically important creatures in their environment. Indeed, some elephant and rhino populations are on track to be locally extinct within the next decade.

If you are reading this, you may already be aware of these facts. But you might not know that wildlife trafficking(走私) not only threatens the existence of elephants and rhinos but is also leading to extinction of other species, such as tigers, tortoises, sea turtles —and the world’s most trafficked mammal—pangolins.

Pangolins are the only mammals that are entirely covered in tough scales(鳞), which makes them look very strong. But actually they are endangered mammals. There are eight different species of pangolins, four in Asia and four in Africa, and all are threatened with extinction. Although pangolins are protected throughout most of the countries where they live, high demand in East Asia, where the delicious pangolin meat is considered a delicacy and where their scales are used in traditional medicines, is driving an illegal trade in both live animals and pangolin parts. The number of pangolin trafficking is shocking. Experts believe that over the last 10 years more than 1 million pangolins were taken from the wild. It is estimated that between 40,000 and 81,250 pangolins were killed for the illegal trade in 2013 alone.

In February, the United States released a plan to deal with wildlife trafficking, which lays out the steps we will take to fight the illegal trade in wildlife, including pangolins. We are strengthening the carrying out of the plan; building international cooperation and contribution to protect wildlife; raising awareness to drive down the demand that is fuelling the illegal trade.

Get involved and remember World Wildlife Day (March 3) by spreading the plan. Use social media and tell everyone that now is the time to get serious about wildlife crime and end the demand that threatens species, big and small, from the huge elephant to the shy pangolin.

El Nino, a Spanish term for “the Christ child”, was named by South American fisherman who noticed that the global weather pattern, which happens every two to seven years, reduced the amount of fishes caught around Christmas. El Nino sees warm water, collected over several years in the western Pacific, flow back eastwards when winds that normally blow westwards weaken, or sometimes the other way round.

The weather effects both good and bad, are felt in many places. Rich countries gain more from powerful Nino, on balance, than they lose. A study found that a strong Nino in 1997-98 helped American’s economy grow by 15 billion, partly because of better agricultural harvests: farmers in the Midwest gained from extra rain. The total rise in agricultural incomes in rich countries is greater than the fall in poor ones.

But in Indonesia extremely dry forests are in flames. A multi-year drought (干旱) in south-east Brazil is becoming worse. Though heavy rains brought about by El Nino may relieve the drought in California, they are likely to cause surface flooding and other disasters.

The most recent powerful Nino, in 1997-98, killed around 21,000 people and caused damage worth $36 billion around the globe. But such Ninos come with months of warning, and so much is known about how they happen that governments can prepare. According to the Overseas Development Institute (ODI), however, just 12% of disaster-relief funding in the past two decades has gone on reducing risks in advance, rather than recovery and rebuilding afterwards. This is despite evidence that a dollar spent on risk-reduction saves at least two on reconstruction.

Simple improvements to infrastructure (基础设施) can reduce the spread of disease. Better sewers (下水道) make it less likely that heavy rain is followed by an outbreak of the disease of bad stomach. Stronger bridges mean villages are less likely to be left without food and medicine after floods. According to a paper in 2011 by Mr Hsiang and co-authors, civil conflict is related to El Nino’s harmful effects—and the poorer the country, the stronger the link. Though the relationship may not be causal, helping divided communities to prepare for disasters would at least reduce the risk that those disasters are followed by killing and wounding people. Since the poorest are least likely to make up for their losses from disasters linked to El Nino, reducing their losses needs to be the priority.

The world itself is becoming much smaller by using modern traffic and modern communication means. Life today is much easier than it was hundreds of years ago, but it has brought new problems. One of the biggest problems is pollution. To pollute means to make things dirty. Pollution comes in many ways. We see it, smell it, drink it and even hear it.

Man has been polluting the earth. The more people, the more pollution. Many years ago, the problem was not so serious because there were not so many people. When the land was used up or the river was dirty in one place, man moved to another place. But this is no longer true.

Man is now slowly polluting the whole world.

Air pollution is still the most serious. It’s bad for all living things in the world, but it is not the only one kind of pollution. Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us angry more easily.

Many countries are making rules to fight pollution. They stop people from burning coal in houses and factories in the city, and from putting dirty smoke into the air. Pollution by SO₂ is now the most dangerous kind of air pollution. It is caused by heavy traffic. We are sure that if there are fewer people driving, there will be less air pollution.

The earth is our home. We must take care of it. That means keeping the land, water and air clean. And we must take care of the rise in pollution at the same time.

Pigeons may only have a brain the size of a thimble (顶针), but it appears that pigeons can categorize and name objects in the same way human children learn new words.

A new study from the University of Iowa has shown that the birds are capable of learning to categorize 128 different photographs into 16 basic categories.

Scientists taught three pigeons to sort out different kinds of dogs or types of shoes, for example by using a particular symbol in exchange for a reward. When they were shown black and white pictures of previously unseen dogs or shoes, the birds were able to correctly match these with the corresponding symbols.

The scientists behind the project say this is a similar approach taken by young children when they are first learning words for objects. However, the researchers said it took their birds around 40 days to perfect the task of learning just 16 categories.

Professor Edward Wasserman, who led the work, said: “Our birds’ rate of learning appears to have been quite slow. Would children learn faster than pigeons? Almost certainly. However, our pigeons came to the experiment with no background knowledge at all. Thus, the more relevant comparison group may be newborn babies, who indeed take 6–9 months to learn their first words.”

Writing in the journal Cognition, the researchers said their experiment was a very simple mirror of the way children are taught words — by their parents pointing to pictures and asking them to name the object.

Pigeons are known to be smarter than many birds. Professor Bob McMurray, who also took part in the study, said the results showed that human learning is not as unique as was previously believed.

He said: “Children are facing a huge task of learning thousands of words without a lot of background knowledge to go on. For a long time, people thought that such learning is special to humans. What this research shows is that the ways in which children solve this huge problem may be shared with many species.

A build-it-yourself solar still（蒸馏器） is one of the best ways to obtain drinking water in areas where the liquid is not readily available. Developed by two doctors in the U.S. Department of Agriculture, it’s an excellent water collector. Unfortunately, you must carry the necessary equipment with you, since it’s all but impossible to find natural substitutes. The only components required, though, are a 5＇5＇ sheet of clear or slightly milky plastic, six feet of plastic tube, and a container — perhaps just a drinking cup — to catch the water. These pieces can be folded into a neat little pack and fastened on your belt.

To construct a working still, use a sharp stick or rock to dig a hole four feet across and three feet deep. Try to make the hole in a damp area to increase the water catcher’s productivity. Place your cup in the deepest part of the hole. Then lay the tube in place so that one end rests all the way in the cup and the rest of the line runs up — and out — the side of the hole.

   Next, cover the hole with the plastic sheet, securing the edges of the plastic with dirt and weighting the sheet’s center down with a rock. The plastic should now form a cone(圆锥体) with 45-degree-angled sides. The low point of the sheet must be centered directly over, and no more than three inches above, the cup.

   The solar still works by creating a greenhouse under the plastic. Ground water evaporates (蒸发) and collects on the sheet until small drops of water form, run down the material and fall off into the cup. When the container is full, you can suck the refreshment out through the tube, and won’t have to break down the still every time you need a drink.

  阅读下面短文，从短文后各题所给的四个选项(A, B, C和D）中，选出可以填入空白处的最佳选项飞并在答题卡上将该项涂黑。