Alpacas(羊驼) are members of the camel family, having lived in South America for thousands of years. Their fur gives the animals a teddy bear_like appearance. Alpacas are too small to be used as animals of burden but are valued only for their fur. Generally, their lifespan is around 15 to 20 years.

    Alpacas are social animals that live in family groups made up of a male, females and their young. They are gentle, elegant, curious, intelligent and observant. They are safe and pleasant to be around, moving gracefully and slowly around the field, and are therefore unlikely to run into or over anyone, even small children. Occasionally, an alpaca will spit snd kick, but the soft padded(有爪垫的) feet usually do little more than just“get your attention”.

    Because these animals are environmentally friendly and need so little grass and food, you can usually raise from two to eight alpacas on an acre of land with grass or hay. A single, 60 pound bale(大捆) of hay can generally feed a group of about 20 alpacas for one day. Alpacas also require access to plenty of fresh water to drink.

    Alpaca fur is used for making knittedd and woven(编织) items, just as sheep's wool is. These items include blankets, sweaters, hats, gloves, scarves, a wide variety of textiles(针织品) in South America, and sweaters, socks, coats and bedding in other parts of the world. The fur comes in more than 52 natural colors as classified in Peru, 12 as classified in Australia and 16 as classified in the United States.

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Foreign visitors to the UK might be disappointed when they learn that not everyone there speaks like Harry Potter and his friends. Usually, there's an assumption by many non-Brits that everyone in Britain speaks with what's known as a Received Pronunciation (RP, 标准发音) accent, also called "the Queen's English". However, while many people do talk this way, most Britons speak in their own regional accents.

    Scouse, Glaswegian and Black Country – from Liverpool, Glasgow and the West Midlands – are just three of the countless non-RP accents that British people speak with. There are even differences in accents between towns or cities just 30 kilometers apart. What is even more disappointing is that not speaking in a RP accent may mean a British person is judged and even treated differently in their everyday life.

    In a 2015 study by The University of South Wales, videos of people reading a passage in three different UK accents were shown to a second group of people. The group then rated how intelligent they thought the readers sounded. The lowest-rated accent was Brummie, native to people from Birmingham, a city whose accent is considered working class.

    However, there is no need to be disappointed though you are not speaking in an RP accent. In fact, doing the opposite may even give you strength.

Kong Seong-jae, 25, is an internet celebrity from Seoul. After studying in the UK, he picked up several regional accents. He's now famous for his online videos, where he shows off the various accents he's learned. "British people usually get really excited when I use some of their local dialect words, and they become much friendlier. I think it makes a bit of bond between local people and foreigners to speak in their local accent," he said.

    So if you're working on perfecting your British accent, try to speak like someone from Liverpool, Glasgow or Birmingham. You may not sound like Harry Potter, but you are likely to make more friends.

    This may be music to your ears. Researchers P. Jason Rentfrow and Samuel Gosling gave 3,500 people a personality（人格、个性）quiz. "We found that the musical styles people like are closely linked to their personalities," Gosling says.

    RAP/HIP-HOP

    Known for their quick speech, some rappers can say more than 700 syllables（音节）a minute! If you like rap/hip-hop, you are energetic and have a way with words. You put a fresh spin on things, whether it's new moves on the dance floor or your hip style.

    CLASSICAL

    In the 18th century, classical musicians were like rock stars. Beethoven and Mozart, for example, played in crowded concert halls. If you like classical, you are open to new ideas and like debating with friends. Creative and imaginative, you can easily spend many hours scrapbooking（剪贴）, writing or painting.

    COUNTRY

    Country music came from the folk songs of English, Scottish, and Irish settlers of the southeastern United States. If you like country, you express your opinions well, which makes you the ideal class president or team captain. Traditional and loyal, you enjoy spending time with your family.

    POP

    Pop music is designed to attract almost everyone, and it does. Each year, the industry brings in about 30 billion dollars! If you like pop, you are attractive to your friends. You can make big things happen, like planning for a huge party or inspiring your team to victory.

    ROCK/ALTERNATIVE

    In the 1950s, rock music created a brand-new culture. Teenagers, for the first time, had an identity separate from adults and children. If you like rock/alternative, you are a risk-taker who never accepts no for an answer. You rise to any challenge, like doing very well in a big exam or landing the lead in the school play.

    If these personality profiles（人格剖析）don't match you, that's OK. These are just for fun.

    The full moon climbs over the eastern horizon (地平线) and hangs like a huge orange globe in the sky. A few hours later, the moon is overhead but seems to have changed. The huge orange globe has become a small silver disk. What has happened? Why has the orange color disappeared? Why does the moon seem so much smaller and farther away now that it is overhead?

    The moon appears orange on the horizon because we view it through the dust of the atmosphere. The overhead moon does not really shrink (缩小) as it moves away from the horizon. Our eyes inform us that the overhead moon is farther away. But in this position the moon is actually closer to our eyes than when it is near the horizon.

    The change in size is a trick our eyes and minds play on us. When the moon is low in the sky, we can compare its size with familiar objects. It is easy to see that the moon is much larger than trees or buildings, for example. When the moon is high in the sky, however, it is hard to compare it with objects on earth. Compared to the vastness of the sky, the moon seems small.

    There is another reason why the moon seems to shrink. We are used to staring at objects straight ahead of us. When an object is difficult to see, our eyes have to try to focus on it. When we move our heads back to look up, we will try hard again. Looking at something from an unaccustomed position can fool you into believing an object is smaller or farther away than it is. However, scientists do not yet understand completely why the moon seems to shrink as it rises in the sky.

    Self­control is the ability to regulate and adjust responses in order to avoid undesirable behaviors, increase desirable ones, and achieve long­term goals. Common goals such as losing weight, exercising regularly, eating healthy food, giving up bad habits, and saving money are just a few worthwhile ambitions that people believe require self­control.

    One 2011 survey conducted by the American Psychological Association found that 27 percent of subjects identified a lack of willpower as the primary factor keeping them from reaching their goals. Researchers have found that people who have better self­control tend to be healthier and happier. In one experiment, students who exhibited greater self­control had better grades and higher test scores, and were more likely to be admitted to a competitive academic program. The study also found that when it came to academic success, self­control was a more important factor than IQ scores.

    The psychologist Walter Mischel conducted famous experiments in 1975 that were related to delayed gratification. In these experiments, children were offered a choice: they could choose to eat one treat right away, usually a cookie or a candy or they could wait for a brief period of time in order to get two treats. At this point, the researcher would leave the child alone in a room with a single treat. Not surprisingly, many of the kids chose to eat the single treat the moment the experimenters left the room. However, some of the kids were able to wait for the second treat.

    Based on his research, Mischel proposed what he  referred to as a "hot­and­cool" system to explain the ability to delay gratification. The hot system refers to the part of our willpower that is emotional and impulsive ( 冲动的) and urges us to act upon our desires. The cool system is the part of our willpower that is rational ( 理性的) and thoughtful, and enables us to consider the consequences of our actions in order to resist our impulses.

    Self­control is an important skill that allows us to regulate behavior in order to achieve our long­term goals. Research has shown that self­control is not only important for goal attainment, and people with greater willpower also tend to do better on all sides.

    NASA has a new job listing, and it's no joke. The US space agency is looking for a "joker" to join their planned mission to Mars.

    A mission to Mars is no laughing matter. On average, the red planet is 140 million miles (225 million kilometers) away from Earth. A trip there would take around eight months in a small spacecraft. And Mars has a communications delay of 20 minutes. This means that astronauts will have to wait 20 minutes for a reply, when an emergency happens.

    "When you're living with others in a confined space for a long period of time, such as on a mission to Mars, problems are likely to occur," Jeffrey Johnson, a scientist at the University of Florida, told The Guardian.

    This is probably why NASA wants an astronaut with a sense of humor. "These are people that have the ability to pull everyone together," Johnson said.

    In stressful situations, perhaps humor is a way to know we aren't alone. By laughing together, we share our stress. Then we can focus on our jobs instead of just worrying.

    There are other examples of team "clowns". One example is the journey to the South Pole led by Norwegian explorer Roald Amundsen. It was a difficult journey full of danger. Adolf Lindstrom, a cook at Amundsen's team, was a "clown". He made people laugh through the whole journey. Amundsen later wrote that Lindstrom was the most valuable member of the team.

    But if you're hoping that your favorite TV comedian will fly to Mars, that probably won't happen.

    "Being funny won't be enough to land somebody the job," Johnson said. "They also need to be an excellent engineer."

    Besides, they must be in top physical condition.