Cleaning your plate may not help feed hungry children today, but the timeworn advice of mothers everywhere may help reduce food waste from the farm to the fork, help the environment and make it easier to feed the world's growing population.

    Hard data still being collected, but experts in Chicago said about 30% to 50% of the food produced in the world goes uneaten. The average American throws away 33 pounds of food each month—about $40 worth, which means each person throws away almost 400 pounds of food. The US Department of Agriculture says that 23% of eggs and an even higher percentage of produce ends up in the trash.

"We forget we have all these fresh fruits and vegetables, and at the end of the week we have to throw them away", said Esther Gove, a mother of three young children in South Berwick, Maine. "Now, I don't buy as much fresh produce as I used to."

    But the effect of food waste arrives far beyond the kitchen. Agriculture is the world's largest user of water, a big consumer of energy and major emitter of greenhouse gases during production. Experts say reducing waste is a simple way to cut stress on the environment and can ease pressure on farmers, who will be called on to feed an expected 9 billion people around the world in 2050, compared with nearly 7 billion today.

    No matter how sustainable (可持续的) farming is, if the food's not getting eaten, it's not sustainable and it's not a good use of our resources. In richer nations, fruit and vegetables end up in the trash because they aren't pretty enough to meet companies' standards, have gone bad in a home refrigerator or aren't eaten at a restaurant. In developing countries, much food spoils before it gets to market due to poor roads and lack of refrigeration. High food prices are another reason, since some people can't afford the food that's produced.

    When you see someone you know, the easiest way to recognize them is by their face—but not everyone can do this. Many people have prosopagnosia, or face blindness, which is a neurological（神经病学的）condition where the part of the brain that recognizes faces fails to develop. It can stop people recognizing partners, family members, friends or even their own reflection. It was once thought to be caused by brain injury (acquired prosopagnosia) but now a genetic link has been proved (development prosopagnosia).

    Acquired prosopagnosia is a very rare but as many as one in 50 people may have developmental prosopagnosia. There's no specific treatment, but training programmes are being developed to help improve facial recognition.

    For many, the situation can be dangerous. I've heard stories of people being robbed by strangers claiming to be family members, or of children wandering off strange men.

    It was only is this century that researchers began to realize exactly how many people in this world were quietly living with the condition.

    Like a blind person who can recognize family members by their footsteps, prosopagnosics are forced to develop unusual ways of discovering who it is they're meeting or talking to. From the obvious markers like hair and voice, to the way one sits, stands or walks, they rely on dozens of means to get through ordinary life.

    Faces are an important part of identity. Not to be recognized feels terrible—it's as if you've been overlooked, like someone's saying you don't matter. But it's nothing to the pain of knowing that you're hurting people's feelings constantly, and yet being completely unaware that you're doing it in the moment. To be alienated（隔离的）from the world of faces is a strange position to be in, but I'm comforted by the thought that articles like this will do a little to help people forgive me and others like me.

    Do you have a spare room in your house? What about a driveway for your car? Both of these can help you make money. Many people who are feeling the pinch are taking advantage of what's been called the “sharing economy”.

Perhaps the best-known example of a company in this field is Airbnb—an American web business which allows you to rent out your spare room to holidaymakers. It says it operates in 34,000 cities and it has over 1,500,000 listings.It seems to have concerned the market!

A British company is doing something with parking spaces. JustPark's founder, Anthony Eskinazi, says,“When I had the original idea, Ispotted a driveway close to a sports stadium. It would have been so convenient if I could have just parked in that driveway rather than in commercial car park.” And he has a big clientele（客户）:around 20,000 people have advertised their spaces on the site, and he says around half a million drivers use it. There are other sites doing very similar things, like Uber and Lyft—these let drivers share their cars with other passengers. Any driver knows how valuable a place to park is .A church near Kings Cross in central London has apparently made over £200,000 by renting out space in its yard to travelers!

    Because this is a new business world, those rules aren't there yet and many people are happy to share...as long as it pays!

    But the sharing economy has its critics: the competitors of these new companies. People who run things like traditional B&B, commercial car parks and taxi services are afraid of ending up out of pocket. And there is another issue: regulations on these new business are unclear. How will renting out your driveway affect your neighbor?

    Downloading music over the Internet is pretty common among high school and college students. However, when students download and share copyrighted music without permission, they are against the law.

    A survey of young people's music ownership has found that teenagers and college students have an average of more than 800 illegally copied songs each on their digital music players. Half of those surveyed share all the music on their hard drive (硬盘), enabling others to copy hundreds of songs at any one time. Some students were found to have randomly linked their personal blogs to music sites, so as to allow free trial listening of copyrighted songs for blog visitors, or adopted some of the songs as the background music for their blogs. Such practices may be easy and free, but there are consequences.

    Sandra Dowd, a student of Central Michigan University, was fined US $7,500 for downloading 501 files from Lime Wire, a peer-to-peer file sharing program. Sandra claimed that she was unaware that her downloads were illegal until she was contacted by authorities. Similarly, Mike Lewinski paid US $4,000 to settle a lawsuit（起诉）against him for copyright violation (违反). Mike expressed shock and couldn't believe that this was happening to him. “I just wanted to save some money and I always thought the threat was just a scare tactic(战术).” “You know, everyone does it,” added Mike.

    The RIAA （Recording Industry Association of America）, the organization that files lawsuits against illegal downloaders, states that suing (控告) students was by no means their first choice. Unfortunately, without the threat of consequences, students are just not changing their behavior. Education alone is not enough to stop the extraordinary growth of the illegal downloading practice.

    The best-known example of external( 外部的)influence causing language change is the "Americanization" of world culture, which has caused English words to appear in city streets all over the world. The effect is most noticeable in pop music. Foreign groups often record in English, and the words are picked up and repeated in the same language everywhere, even by children who otherwise have little or no command of the language. I once met a Brazilian child of about ten who could count 'one, two, three', but only by adding the words 'o'clock, four o'clock rock 'at the end.

Some people are often strongly critical of the influence of English on their language — especially when an English word replaces a traditional word. In 1977, France passed a law banning the use of English words in official situations if an equivalent( 意义相同的)French expression existed — but the law seemed to be honored more in the breaking than in the observing. Some other countries have considered introducing a similar law despite the evidence that such laws have very little effect, and that the arrival of loan words( 外来词) can greatly enrich a language (as indeed in the case of English itself, which has a long history of welcoming foreign words).

    However, not everyone is critical. In particular, commercial firms and advertisers are well aware of the potential selling power that the use of English vocabulary can bring. In Japan, English is even used in television commercials, despite the fact that the majority of viewers would not understand exactly what was being said: the excellence implied by the mere use of English is apparently enough to command the strategy to the advertisers.

    Most of the influence of English is upon the vocabulary of foreign languages, but surveys are slowly bringing to light several cases where word order or word structure has been affected. Sentences of the type “The book sells well”, using an active construction for a passive meaning, have begun to appear in Danish (Bogen soelger godt). Several languages keep the English plural ending when they make use of a loan word, and do not translate it into the native form, e.g. drinks. There are many other such cases.

    In recent years more and more Chinese schoolchildren are required to wear uniforms at school. Do American children wear school uniforms? In fact, American schoolchildren often wear uniforms if they attend religious or other private schools. Most public schools do not require uniforms. But over the last ten years or so, more of them have moved in that direction, including high schools. Another option is that students may just have to dress alike—for example, white shirts and dark colored pants or skirts. Even schools that do not require uniforms generally have a dress rule about what they consider acceptable. Schools commonly forbid clothing that shows images or words causing displeasure, or simply too much skin. Hats may be forbidden because, for example, different colors may be connected with bad guys.

    Some parents like the idea of uniforms. Some say it means they do not have to spend much on clothing for their kids. Others, though, argue that uniforms represent an unnecessary cost.

    There are also debates about whether uniforms or other dress rules go against civil rights. Students and parents have taken legal action against school dress requirements. Several years ago, a middle school was asked to stop its dress rule unless families had a way out of it. The American Civil Liberties Union of Northern California brought the case for the families of several students who had been punished by the school. Most attention centered on a girl who wore socks with the Tigger character from Winnie the Pooh. The school said its clothing policy, including no pictures of any kind, was needed to control a growing problem with gangs. The families argued that the policy went against free speech rights as protected by the United States and California constitutions.

    The United States Supreme Court says student expression is protected as long as it does not harm the work and the rule of a school. But some educators believe dressing alike helps improve student learning. They believe that uniforms help create a sense of unity and reduce the risk of fights. They also say uniforms make it easier for security reasons to tell if someone belongs to the school or not.