Computers have beaten human world champions at chess and, earlier this year, the board game Go. So far, though, they have struggled at the card table. So we challenged one AI to a game.

Why is poker(扑克)so difficult? Chess and Go are “information complete” games where all players can see all the relevant information. In poker, other players' cards are hidden, making it an “information incomplete” game. Players have to guess opponents' hands from their actions—-tricky for computers. Poker has become a new benchmark for AI research. Solving poker could lead to many breakthroughs, from cyber security to driverless cars.

    Scientists believe it is only a matter of time before AI once again vanquishes humans, hence our human-machine match comes up in a game of Texas Hold's Em Limit Poker. The AI was developed by Johannes Heinrich, researcher studying machine learning at UCL. It combines two techniques: neural(神经的)networks and reinforcement learning(强化学习).

    Neural networks, to some degree, copy the structure of human brains: their processors are highly interconnected and work at the same time to solve problems. They are good at spotting patterns in huge amounts of data. Reinforcement learning is when a machine, given a task, carries it out, learning from mistakes it makes. In this case, it means playing poker against itself billions of times to get better.

    Mr Heinrich told Sky News: “Today we are presenting a new procedure that has learned in a different way, more similar to how humans learn. In particular, it is able to learn abstract patterns, represented by its neural network, which allow it to deal with new and unseen situations.”

    After two hours of quite defensive play, from the computer at least, we called it a draw.

    Are you nervous about climbing because you think it's too dangerous?Do you feel you're not fit enough to climb?Do you know how to start climbing?

    Let's consider the idea that climbing is dangerous.Being afraid is natural,but if you use suitable ropes and other climbing equipments you will feel completely safe.Climbers are usually very careful because they know what they are doing is dangerous.Accidents may happen,but when they do,they tend to attract a lot of publicity.As a result, people think there are many more accidents than there are in reality.

    You cannot expect to start climbing straight away.Climbing is a challenge and challenges take time.It is necessary first of all that you achieve a good level of fitness.Begin as soon as you become interested in climbing—go to the gym,go swimming,take up jogging and continue to do so throughout your training period.

    Discover as much as you can about climbing.Visit the library and find books especially for beginners or buy climbing magazines and look for articles which describe your situation.Look up information on the Internet.Find out about equipment,methods and places to go.

    Next,take a course on a climbing wall.There are plenty of climbing walls all over the country which have trained and qualified people as instructors.Call your local leisure centre to find out if there is one in your area.These training sessions are a quick way to get experience and you are likely to meet other beginners.After this,you can do an outside course or join a club where you can meet climbers of all abilities and eventually join in group-climbing events.

    At first you may not understand the importance of a good training period,but after you have completed your first climb and you are standing safely at the top of a rock feeling thrilled,then you will know it was the right thing to do.

    Sharon, Aged 22

    The most important thing to keep in mind when going into high school is to be yourself. Besides, I don't know what your middle school was like, but high school teachers will not care about things such as how much homework you already have in one night. It's best to just learn to deal with things and manage your time wisely so you can achieve everything you need to.

    Frank, Aged 21

    I think almost every kid feels both nervous and excited before their first day. You will probably love it. I know I did. You should join some sports or activities that will make your high school experience more enjoyable. Good luck!

    Eddie, Aged 20

    When I started high school I was really nervous too, especially since I had been homeschooled all through middle school and didn't really know anyone. I suppose the best advice would be to just relax. The first couple of days can be a little bit hard, but things will become easier before you know it.

    David, Aged 19

    I'm not going to lie. The first day is kind of frightening(令人恐惧的). But you'll get used to it. Don't be afraid of anyone; upperclassmen will pick on you more if you let them know you're afraid. Just take it easy. Making some friends and staying with them will greatly help you get used to high school quickly. After the first week it's really not bad at all. Don't worry.

    A popular saying goes, “Sticks and stones may break my bones, but words will never hurt me.” However, that's not really true. Words have the power to build us up or tear us down. It doesn't matter if the words come from someone else or ourselves— the positive and negative effects are just as lasting.

    We all talk to ourselves sometimes. We're usually too embarrassed to admit it, though. In fact, we really shouldn't be because more and more experts believe talking to ourselves out loud is a healthy habit.

    This “self-talk” helps us motivate ourselves, remember things, solve problems, and calm ourselves down. Be aware, though, that as much as 77% of self-talk tends to be negative. So in order to stay positive, we should only speak words of encouragement to ourselves. We should also be quick to give ourselves a pat on the back. The next time you finish a project, do well in a test, or finally clean your room, join me in saying “Good job!”

    Often, words come out of our mouths without us thinking about the effect they will have. But we should be aware that our words cause certain responses in others. For example, when returning an item to a store, we might use warm, friendly language during the exchange. And the clerk will probably respond in a similar manner. Or harsh (刻薄的) and critical language will most likely cause the clerk to be defensive.

    Words possess power because of their lasting effects. Many of us regret something we once said. And we remember unkind words said to us! Before speaking, we should always ask ourselves: Is it true? Is it loving? Is it needed? If what we want to say doesn't pass this test, then it's better left unsaid.

    Words possess power: both positive and negative. Those around us receive encouragement when we speak positively. We can offer hope, build self-esteem (自尊) and motivate others to do their best. Negative words destroy all those things. Will we use our words to hurt or to heal? The choice is ours.

    After the examination, the doctor told my parents my sight would get worse and that I would lose my sight finally. On the way home from hospital, no one said a word. One day, would I only imagine the scenery beyond the glass rather than see it?

    That September, I entered middle school. Most nights I had homework that included an armful of books to read. To keep up with other children, I took great trouble to finish the task. With my nose a couple of inches from the page, I was tired easily. What's worse, after I had read several pages on my own, the words slipped off the page into inky pools.

    However, then I did not have audio books and electric devices like kids do now. Instead, Mum volunteered to read out loud. Mum worked part-time, cleaned the house, cooked and spent time with Grandma. In spite of being so busy, she showed up in my room like clockwork. She put on her reading glasses. Mum always thought those glasses made her look old. To me, she looked like a teacher.

    In my room, Mum's voice raced with the ticking of the clock. Being forced to focus on listening, I found a way to keep my marks up and compete with the other kids. When the teacher asked a question, I raised my hand with confidence. Teachers praised me for having a good memory. Reading removed my fear for my failing sight, reading also made me curious about other people's challenges and how they managed. Though I could not use my eyes to fix on each passage, my mind lit up with every new book.

    True to what the doctor said, the worst came, but thanks to Mum, my sense of hearing now allows me to “see”. This was the most precious gift from a mother to her child.

    When it comes to the most famous 20^th century painters of the United States, Grandma Moses should be mentioned, although she did not start painting until she was in her late seventies. As she once said to herself:" I would never sit back in a rocking chair, waiting for someone to help me." No one could have had a more active old age.

    She was born on a farm in New York State, one of five boys and five girls. At 12 she left home and was in domestic service until at 27 she married Thomas Moses, the hired hand of one of her employers. They farmed most of their lives, first in Virginia and then in New York State, at Eagle Bridge. She had ten children, of whom five survived; her husband died in 1927.

    Grandma Moses painted a little as a child and made embroidery(刺绣) pictures as a hobby, but only changed to oils in old age because her hands became too stiff(僵硬的) to sew and she still wanted to keep busy and pass the time. Her pictures were first sold at the local drugstore and at a market and were soon noticed by a businessman who bought all that she painted. Three of the pictures were exhibited(展览) in the Museum of Modern Art, and in 1940 she had her first exhibition in New York. Between the 1930's and her death, she produced some 2,000 pictures: careful and lively portrayals of the country life she had known for so long, with a wonderful sense of color and form. "I think really hard till I think of something really pretty, and then I paint it" she said.