Many people believe that you lose the ability to learn new languages as you get older. Language experts, however, will tell you that you're never too old to learn a new language. As you get older, it can be more difficult to learn a new language, though.

    Children and adults learn new languages in different ways．For children, language is their life. They study for thousands of hours every year, because they need to learn languages to become part of their communities. Adults, on the other hand，are already part of a language community. Learning a new language means becoming part of another language community, and adults seldom get the chance to practice as much as young children do.

    Moreover, children learning a new language are expected to make mistakes. This gives them freedom when learning to be daring and confident. Adults, however, often feel pressured to be perfect when learning a new language. This can discourage many people and make it even harder to learn a new language.

    Research has shown that children who learn a new language when they are very young will not be likely to have a “foreign” accent when speaking a different language. Some scientists also believe that it can take up to 10,000 hours of study to master a new language. This can be difficult for adults to achieve, but young children can accumulate(积累) those hours over several years as they grow up.

    When young children learn a new language, they come to see multiple languages as a “normal” part of society. This mindset (思维模式) helps them learn a new language without feeling like they're doing something unusual or “too hard”.

    So if you want to learn a new language, go for it! It's never too late to learn a new language. If you're older, it may take more work, but it can be done. If you're a young child, though, now is the time to step out and learn a new language!

    If you see a group of people dancing and singing on the street or in the railway station, you don't need to feel surprised. They are a flash mob(快闪族). Who are they Are they mobs? Don't be confused by their name. Actually, a flash mob is a group of people who gather suddenly in a public place, do something unusual for a brief period of time, and then quickly disappear.

    They are usually organized with the help of the Internet or other digital communications networks. The messages may be sent to friends, who send to more people. At a predetermined time, they gather and perform some activities such as exchanging books, coming together to look at the sky, waving their hands and yelling something at the top of their voice for 30 seconds. Then, they quickly disappear before the police can arrive Using mobile phones, the flash mob can change its place if the first one has been cancelled for any reason.

    Bill Wasik, senior editor of Hamper's Magazine, organized the first flash mob in Manhattan in May 2003 and the first successful flash mob gathered on June 3, 2003. Wasik claimed that he created the flash mob as a social experiment designed to laugh at fashion seekers and stress the cultural atmosphere of wanting to be an insider or part of "the next big thing”.

    Flash mob gatherings can sometimes shock people. Such an activity might seem amusing and magical, but it also might frighten people who are not aware of what is taking place. Undoubtedly, flash mob can serve as good political tools and have great potential, such as using flash mob to advertise a product.

    The flash mob is now becoming more and more popular. People use it to do many things. Flash mobs give people from all walks of life an opportunity to come together to create a memory.

    We've all experienced that feeling that comes when your phone makes a sound to tell you that its battery level is low. It often comes at the worst times – when you're out on a trip and don't have a charger, or when you're expecting an important phone call.

    Indeed, this feeling is so common that South Korean electronics manufacturer LG has given it a name: low battery anxiety.

    According to a survey of 2,000 US adults conducted by the company last year, 90 percent of respondents said that they panic if their battery level reaches 20 percent or lower.

    And last month, UK telecommunications service provider 02 found that around 15.5 million Britons live in “constant fear” of their mobile phones running out of power, according to a survey by the company.

    “The problem is not about being unable to make calls, but is rooted in the fact that smartphones are now where we store digital memories,” noted the Daily Mail.

    However, battery worries don't just affect smartphone lovers. Many owners of electric vehicles also suffer from so-called “range anxiety”. This refers to the concern that the vehicle may not make it to its destination before the power runs out.

    Meanwhile, it isn't just low power that people worry about. A study carried out by South Korea's Sungkyunkwan University and China's City University of Hong Kong found that many of us also worry about not having constant access to our phone.

    This condition is known as nomophobia, short for “no mobile phone phobia（恐惧症）”. Symptoms include feeling uncomfortable when access to one's phone isn't possible, being unable to turn off your phone, and constantly topping up the battery to make sure it never dies.

    So, why do so many people treat their smartphone with such importance? The underlying reason may be that they keep us connected to the people around us, and if we're unable to use our phone, we feel like we're cut off from our social life.

    With products with bigger batteries being released all the time though - such as Xiaomi's Mi Max smartphone range or Tesla's Model S cars – battery anxiety may hopefully soon be a thing of the past.

    As scientists in the Netherlands tried to figure out how to build a super flying robot, they learned from one of nature s flyers: the humble fruit fly(果蝇).And by building this robot, they've gained new insights into how the fly carries out one of its dangerous tasks.

    The robot is called the DelFly Nimble Its wingspan(冀展)is about a foot wide. It has four wings that can beat at 17 times per second, which appear very delicate because they're made of the same material as space blankets.

    In the previous designs, they always had a tail, like a traditional airplane tail, said the robots main designer Matej Karasek. He's based at the Micro Air Vehicle Laboratory at Delft University of Technology in the Netherlands, and he and his colleagues published their findings on Thursday in Science

    “In the previous generations", he said, "flapping wings drove the robot forward while the tail helped to guide and stabilize it. But now the DelFly Nimble is completely controlled by the wings. The challenge then was actually combine the control into the wing movement, and that's what we achieved, Karasek said

    In the latest generation. the wings can each move individually or rotate(旋转)around the body of the robot in order to maximize the machine s agility(灵活 ) The robot can remain in one place in the air for about five minutes on a full battery or fly for more than a kilometer"， Karasek said, "And because the scientists are controlling all the movements, they can use the robot to learn more about how fruit flies actually carry out their dangerous tasks, which has caught the attention of biologists.”

    It's nothing unusual for people to multitask nowadays. But the ability to do a number of things at the same time could be different between the two sexes.

    A team of UK researchers recently compared the performances of 120 women and 120 men in a computer test about switching(转换) between tasks of counting and shape recognition.

    Men equalled women when tasks were done one at a time. But when the tasks were mixed up, there was a clear difference. According to the paper published in the journal BMC Psychology, both women and men slowed down and made more mistakes as the switching became more rapid. But men were slower, taking 77 percent longer to answer, while women took 69 percent longer.

    To make the experiment more connected to day-to-day life, researchers tried a second test. A group of women and men were given eight minutes to complete a series of everyday tasks, such as finding restaurants on a map, doing simple math problems, answering a phone call, or deciding how they would search for a lost key in a field.

    Once again, women performed better than men in the test, especially in the key-searching task.

    Where do women get the ability to keep organized under pressure better than men? Researchers believe that it has its origins in evolution(进化). In ancient times, women had to keep an eye on children while cooking meals. Meanwhile, men only needed to focus on hunting.

    However, as with all studies, the results don't necessarily apply to every single person in the world. "We don't mean that men can't multitask, or that only women can," researcher Keith Laws of the University of Hertfordshire, UK, told BBC News. "We are saying that the average woman is better able to organize her time and switch between tasks than the average man."

Gorman is the youngest poet in U. S. history. She became the youth poet laureate (获奖者) of Los Angeles at age 16 in 2014 and the first national youth poet laureate three years later. She has recently completed her studies at Harvard University.

Her mother, Joan Wicks, teaches middle school in Watts. Shuttling among the neighborhoods gave Gorman a window to the world. Her like for poetry dates at least back to the third grade when her teacher read Ray Bradbury's Dandelion Wine to the class.

Gorman is a lot better at it now, but still working on her confidence as a public speaker. "Until two or maybe three years ago, I couldn't say the letter 'r'. Even to this day sometimes I struggle with it. I'd want to say 'girls can change the world', but I can not say so many letters in that statement, so I'd say things like 'young women can shape the globe'."

For Gorman, writing became a cure. "I used writing as a form of self expression to get my word on the page. So the more I recited out loud, the more I was able to teach myself how to pronounce these letters which for so long had been my greatest impediment." Gorman said she also used a song from Miranda's Pulitzer Prize-winning Broadway musical Hamilton to help with her speaking. "But I don't look at my disability as a weakness," said Gorman. "It's made me the performer that I am and the storyteller that I strive to be."

In September, Gorman will release Change Sings, the first of two children's books. The poet says she desires to publish a book "in which kids could see themselves as change-makers in history, rather than just observers".