We once had a poster competition in our fifth grade art class.

    “You could win prizes,'' our teacher told us as she wrote the poster information on the blackboard. She passed out sheets of construction paper while continuing, “The first prize is ten dollars. You just have to make sure that the words on the blackboard appear somewhere on your poster.”

    We studied the board critically. Some of us looked with one eye and held up certain colors against the blackboard, rocking the sheets to the right or left while we conjured up our designs. Others twisted their hair around their fingers or chewed their erasers while deep in thought. We had plans for that ten-dollar grand prize, each and every one of us. I'm going to spend mine on candies, one hopeful would announce, while another practiced looking serious, wise and rich.

    Everyone in the class made a poster. Some of us used parts of those fancy paper napkins, while others used nothing but colored construction paper. Some of us used big designs, and some of us preferred to gather our art tidily down in one corner of our poster and let the space draw the viewer's attention to it. Some of us would wander past the good students' desks and then return to our own projects with a growing sense of hopelessness. It was yet another grown-up trick of the sort they seemed especially fond of, making all of us believe we had a fair chance, and then always — always — rewarding the same old winners.

    I believe I drew a sailboat, but I can't say that with any certainty. I made it. I admired it. I determined it to be the very best of all of the posters I had seen, and then I turned it in.

    Minutes passed.

    No one came along to give me the grand prize, and then someone distracted me, and I probably never would have thought about that poster again.

    I was still sitting at my desk, thinking, What poster? when the teacher gave me an envelope with a ten-dollar bill in it and everyone in the class applauded for me.

    Have you ever noticed what happens to an idea once you express it?Just talking about it or writing it down causes you to make it clear in your own mind.How can you use this to increase your brain power?Start writing.

    By putting thoughts into words,you are telling yourself the logic behind what you think,feel,or only partly understand.Often,explaining a thought is the process of understanding.In other words,you increase your brain power by exercising your “explain power”.

    Another benefit of writing is that it helps you remember.Many,if not most,highly productive people are always taking notes.You can try keeping it all in your head,but if you keep a journal of your ideas,the next time you're working on a big project,you'll probably have more success.

    Want to understand a topic?Write a book about it.That's an extreme example,but if you are learning something new,write a letter to a friend about it,and you will understand it better.Want to invent something?Write an explanation of the problem—why you want to solve it,and why it is worth solving,and you're halfway there.

    Writers don't always write because they clearly understand something beforehand.Often,they write about something because they want to understand it.You can do the same.Writing will help bring you to an understanding. Give it a try.

    An absolute description of the threat hanging over the world's mammals,reptiles,amphibians and other life forms has been published by the well-known scientific journal,Nature.A special analysis carried out by the journal indicates that an astonishing 41% of all amphibians on the planet now face extinction while 26% of mammal species and 13% of birds are similarly threatened.

    Many species are already critically endangered and close to extinction,including the Sumatran elephant,Amur leopard and mountain gorilla.But also in danger of vanishing（消失）for the wild,it now appears,are animals that are currently rated as merely being endangered.

    In each case,the finger of blame points directly at human activities.The continuing spread of agriculture is destroying millions of hectares of wild habitats every year,leaving animals without homes,while the introduction of newly-come species,often helped by humans,is also damaging native populations.At the same time,pollution and overfishing are destroying ocean ecosystems.

    "Habitat destruction,pollution or overfishing either kill off wild creatures and plants or leaves them badly weakened," said Derek Tittensor,an ocean ecologist at the World Conservation Monitoring Centre in Cambridge. "The trouble is that in coming decades,the additional threat of worsening climate change will become more and more common and could then kill off these survivors."

    The problem,according to Nature,is worsened because of the huge gaps in scientists knowledge about the planet's biodiversity.Evaluations of the total number of species of animals and plants alive vary from 2 million to 50 million.In addition,evaluations of current rates of species' disappearances vary from 500 to 36,000 a year. "That is the real problem we face," added Tittensor. "The scale of uncertainty is huge."

    In the end,however,the data indicate that the world is heading cruelly towards a mass extinction-which is defined as one involving a loss of 75% of species or more.This could arrive in less than a hundred years or could take a thousand,depending on extinction rates.

    We love the sea. We swim into it, live near it, build beside it, and even imagine about living under the sea. But we're terrified of it, too. For much of our history, we have turned to "hard engineering" to control the marine (海洋) environment and manage its influence on us. We build dams, sea walls and channels. But all these efforts seem to fail. The sea has a habit of taking back its own. And we suffer.

    Johnston, a marine ecologist, is advocating for "blue engineering" — the marine version of the "green engineering" movement on land that has seen nations like Singapore building the walls and roofs of the concrete jungle with plant life.

    We are expanding further into the marine environment. This practice does harm lo marine ecosystems. We're loving the sea to death, but we've not been thinking about design of structures (建筑物) with respect to ecology. Some coastal structures create shade, which reduces the growth of seaweed. Bright lights at night contuse species such as turtles. That's why blue engineering comes in.

    Throughout the world people are starting to turn things around. Researchers with the World Harbour Project are creating tiles (瓦片) similar to the natural structures found on rocky shores with 3D printing technology. These make more attractive homes for marine creatures. Researchers are also actively seeding these tiles with local seaweeds and creatures such as the Sydney rock oyster, which is particularly good at improving water quality. Twelve harbours around the world are taking part in this marine tile experiment, each working with their own unique marine life.

    It's a far cry from, he days when huge number, of old tyres were thrown, into the sea to build "artificial reef" (礁石). Those clumsy early attempts are now costing millions to remove, showing just how far we have yet to go in understanding how best to co-habit with the underwater world.

    China became the first country to clone a monkey using non-reproductive cells, reducing the need to keep lab monkeys and paving the way for more accurate, effective, and affordable animal tests for new drugs.

    By December of 2017, Chinese scientists had created two clone macaques named "Zhong Zhong" and "Hua Hua" by nuclear transferring of somatic cells -- any cell in the organism other than reproductive cells. This was the similar technology used to create the famous clone sheep Dolly in 1996.

    Tetra, a rhesus monkey born in 1999, is the world's first ever-cloned monkey, but it was done using a simpler method called embryo splitting, but it could only generate four cloned offspring at a time and cannot be genetically modified to suit experimental needs, said Pu Muming, an academician at the Chinese Academy of Sciences and the director of Institute of Neuroscience, CAS. "Cloning a monkey using somatic cells has been a world-class challenge because it is a primate（灵长类）that shares its genetic makeup, therefore all of its complexity, with humans." Pu Muming said.

    "For drug and other lab tests, scientists have to purchase monkeys from all over the world, which is costly, bad for the environment and produces inaccurate results because each monkey might have different genes," Pu said. "By cloning monkeys using somatic cells, we can mass produce large numbers of genetically same offspring in a short time, and even change their genes to suit our needs," he added. "This can save time, cut down experiment costs, and produce more accurate results, leading to more effective medicine."

    Sun Qiang, director of the non-human primate research facility at the institute, said most of the drug trials are currently done on lab mice. However, drugs that work on mice might not work or even have severe side effects on humans because the two species are so different. "Monkeys and Humans are both primates, so they are much closely related and testing on Monkeys is supposed to be as effective as testing on humans," he said. This is especially useful in testing drugs for neural diseases such as Parkinson's disease, metabolic and immune system disease, and tumor, he added. "This achievement will help China lead the world research in an international science project related to neural（神经的）mapping of primate brains,"he said. However, bio labs from the United States, Japan, and European countries are also very able, and they will quickly catch up to China after the monkey cloning technology is made public, Sun added." This means we have to innovate continuously and work extra harder this year to stay ahead," he said.

    Language learning apps are very popular now and offer opportunities to learn vocabulary and practice grammar. But there has been a discussion about just how effective such apps can be.

    Among the most popular apps are Duolingo and Busuu. A previous research found positive results on the use of them. But it mainly concentrates on studies with learners who had signed up for language courses and these apps worked as an after-class support, so the results were not always reliable. A recent study of 4,095 Busuu users has been carried out to find out if users can actually learn a language with an app.

    Busuu provides learning materials for 12 different languages. It offers special models where some contents are available for free while some contents are not, We find that its users are an even mix of men and women. More than half consider themselves to be at the beginner level as there is a decrease in users as their language levels go up. Most people use the app because of personal interest, or because they want to study or live abroad. Females tend to use it less often but for longer periods of time than male users.

    Getting any feedback on Busuu depends on whether your answer is correct or not. While it is helpful, this is not the sort of feedback language teachers prefer, as it does not explain why the answer is right or wrong. In spite of this, feedback in the app is very highly rated.

    More than 92% of the people state that the app has met their expectations and 86% consider the app as very good or good. In fact, more than 80% of the users surveyed strongly agree that using the app has helped them improve their knowledge of the language they are learning.

    Besides, language learning apps also create an environment where mistakes are only known to the users, and this can address the performance anxiety that many learners suffer from when asked to speak a foreign language. So language teachers should encourage their students to use them to do the grammar work, leaving precious class time for more language communication.