Elephants might be the most well-known and well-loved animal in African wildlife. But conservation (保护) of the African elephant faces special difficulties. While the elephant population is half of what it was 40 years ago, some areas of Africa have more elephants than populated areas can support. That's why AWF scientists are studying elephant behavior, protecting habitats and finding ways for humans to live peacefully with elephants in Africa.

    Years ago, over hunting and the ivory trade were the biggest threats to elephants survival. Luckily, ivory bans (禁令), hunting rules and protected areas protect elephants from these dangers today.

    The 21st century brings a different challenge to elephant conservation —land-use. Elephants walk across borders and outside parks and other protected areas. So they often destroy crops, causing conflicts (冲突) between local farmers and these big animals.

    Successful conservation strategies (策略) must allow elephants to walk freely in their natural habitats while reducing conflicts between elephants and local people.

    AWF researchers are searching for a way to give both elephants and people the space they need. The AWF is collecting information on elephant habitats and behavior. The information they gather will help to develop the widest possible space for elephants.

    The AWF is helping elephants by protecting their habitats. And they also work with local farmers to improve their life in order to encourage them to protect rather than destroy elephants.

    “Body clocks” are biological methods of controlling body activities. Every living thing has one. In humans, a body clock controls normal periods of sleeping and waking. It controls the times when you are most likely to feel pain. Eating, sleeping and exercising at about the same time each day will help keep body activities normal. But changes in your life—a new job, for example—destroy the balance and thus cause health problems. You could have difficult sleeping, for example. Scientists suggest that early afternoon is the best time of day for physical exercise. They say we are stronger and faster then. Later, about four o'clock, most people feel tired because of the drop of sugar level in the blood. Early afternoon also is a good time to do tasks about memory（记忆） and mathematics. If you must study, however, do it just before going to sleep at night. Scientists say you are more likely to remember information when there is a short delay（耽搁）between study and bed. Body clocks control all the activities from day to day. They also produce changes about every ninety minutes during the day. At the end of such a time period, our ability to think hard begins to become weak. That is the time we are most likely to day-dream. Within fifteen minutes, we are ready to go back to what we were doing.

    China has recently published its first artificial intelligence (AI) textbook for high school students, following a plan by central government last year to include AI courses in primary and secondary school.

    Under the joint efforts by the research center for MOOC at East Normal University and AI startup Sense Time Group, the nine-chapter textbook, named Fundamentals of Artificial Intelligence, was written by eminent scholars from well-known schools nationwide, Xinhua reported on Sunday.

    It includes the history of AI and how the technology can be applied in areas such as facial recognition, auto driving and public security.

    “The textbook focuses not only on basics of AI, also on practical use of AI in daily life,” said Chen Yukun, a professor at East China Normal University, who is also a contributor to the book. At present, about 40 high schools across the country have joined the first batch（批）of AI high education pilot program, by introducing the textbook in curriculum（全部课程）.

    “The AI sector is facing a talent shortage globally. The publication of the book is a breakthrough as it takes AI technology out of the 'ivory tower' and makes it part of high school learning,” said Lin Dahua, a professor at the Chinese University of Hong Kong.

    As early as 2016, the governments had estimated that demand for AI professionals may suddenly increase to 5 million in the coming years.

    “Many industries in the future will benefits from AI technology, so the aim of the related courses should be to let students learn the basic idea and methods of AI,” Lin said.

    China has made significant progress in technological research and development in recent years. According to a report released by US-based venture capital（风险资本）database CB Insights in March, China has for the first time surpassed the United States in equity funding（股权融资）to AI startups.

    If you want to become a fluent English speaker you should take some advice. There are four skills in learning English. They are reading, listening, speaking, and writing. The most important thing you must remember is that if you want to improve your speaking and writing skills, you should first master the skills of reading and listening.

    Read as much as you can. But your reading must be active. It means that you must think about the meaning of the sentence, the meaning of the unfamiliar（不熟悉） words, etc. There is no need for you to pay much attention to grammars or try to understand all the unfamiliar words you come across, but the fact that you see them for the first time and recognize them whenever you see them, for example, in other passages or books, is enough. It would be better to prepare yourself a notebook so you can write down the important words or sentences in it.

    As for listening, there are two choices: besides reading, you can listen every day for about 30 minutes. You can only pay attention to your reading and become skillful at your reading, then you can catch up on your listening. Since you have lots of inputs in your mind, you can easily guess what the speaker is going to say. This never means that you should not practice listening.

    For listening you can listen to cartoons or some movies that are specially made for children. Their languages are easy. Or if you are good at listening you can listen to VOA or BBC programs every day. Again the thing to remember is being active in listening and preferably taking some notes.

    If you follow these pieces of advice, your speaking and writing will improve quickly, and you can be a fluent English speaker one day.

    This year's flu season is pretty scary. To try to minimize the effects, public officials are still urging anyone who hasn't yet gotten their flu shot to get one as soon as possible. However, even if every single person got a shot in the arm, the vaccine(疫苗)—with its excellent 36 percent effectiveness—would not prevent everyone from getting infected with the annoying virus. Knowledge is power, so here's what goes on in your body when you come down with the flu.

    The influenza virus primarily attacks your nose, throat, and the tubes that lead to your lungs. But the flu is so much more than that. Your muscles ache, your head hurts, and your appetite goes down, among other things. To our surprise, almost all of these symptoms have less to do with the virus itself than with your immune(免疫的)response to them. Unfortunately, the very defense you have in place to get rid of the flu is the reason you feel so painful when you recover.

    The virus usually enters through your mouth, typically by way of your hands But it takes a few days for symptoms to set in. While this process might cause some harm to your nose and throat, it's nothing major, and nothing like the symptoms that typically accompany a bad or even mild case of the flu.

    The real fun starts when your immune system begins to fight. Your immune system comes in two parts: the innate system and the adaptive. The innate immune system is essentially an all-purpose tool. As soon as your body senses the presence of any injury or invader (入侵者), the innate immune system launches into action by producing tiny proteins called cytokines and chemokines. The cytokines reproduce almost immediately and start to attack the virus. This increase in immune cells creates an serious inflammation(炎症) throughout the body. But the worst is still to come. Meanwhile, the chemokines work with the adaptive immune system to help create T cells. These cells are a special type of white blood cell that works in a much more specific way: They find the influenza virus, identify what's special about it, and create something unique on their surface that finds and destroys similar invaders.

    Mr. Bean is an internationally recognized comedy character on TV and in films. He constantly gets into awkward and absurd situations, which greatly amuses audiences regardless of their nationalities or culture. The humour is always made clear through a series of simple and funny acts that rely purely on body language, which is universal.

    One of my favourite shows is that Mr. Bean has a meal in a fancy restaurant. After being seated at his table, Mr. Bean takes out a card, writes a few words on it, seals (密封) it in an envelope and places it on the table. After a moment, he looks back at the envelope but this time he looks surprised, as if he did not know it was there. He opens it to find a birthday card and delightedly puts it on the table for everyone to see.

    When he looks at the menu, an astonished look swiftly appears on his face. He takes all the money out of his wallet, counts it and puts it in a saucer (茶托). He then looks from the menu to the money with concern until he finds one thing that makes him smile. Then he orders a dish called "steak tartare". When the dish arrives, he is shocked to discover that "steak tartare" is actually raw hamburger. He makes an attempt to eat it, but it is clear from the look on his face that he finds the taste truly disgusting. He cannot hide his feelings, except when the waiter asks if everything is all right. When this happens, he smiles and nods, indicating that everything is fine. When the waiter is not looking, however, he busies himself hiding the raw meat anywhere he can reach-the sugar bowl, the tiny flower vase, inside a bun (小圆面包) and under a plate. He becomes so desperate in the end that he even hides some inside the purse of a woman sitting near him and throws some down the trousers of the restaurant's violinist!

    I like to watch Mr. Bean on TV, but I wouldn't like to meet someone like him in real life and I certainly wouldn't like to have dinner with him!