A student is learning to speak British English. He wonders: Can I communicate with Americans? Can they understand me? Learners of English often ask: What are the differences between British and American English? How important are these differences?

    Certainly there are some differences between British and American English. There are a few differences in grammar. For example, speakers of British English say “in hospital” and “Have you a pen?” Americans say “in the hospital!” and “Do you have a pen?” Pronunciation is sometimes different. Americans usually sound theirs in words like “bird” and “hurt”. Speakers of British English do not sound theirs in these words. There are differences between British and American English in spelling and vocabulary. For example, “colour” and “honour” are British, “color” and honor” are American.

    These differences in grammar, pronunciation, spelling and vocabulary are not important. However, for the most part, British and American English are the same language.

    “Why do birds sing?” I asked a group of children. “To attract metes(配偶)!” answered a boy. A 4-year-old girl added shyly, “birds sing because they are happy, and they want to make us happy, too.” I think both answers are probably true in a way. If birds sing happily, it shows all is well in the forest: no predators (捕食者) are present, and the birds can feed, sing and do other bird things. The sound of a relaxed robin(知更鸟) singing is easy to understand because it makes us feel this way too—it's a sound that lifts our own hearts when we hear it.

    What happens when a predator comes into their areas? The nearby birds quickly give an alarm call, a short sound that warns, “Danger is coming!” On hearing the sound, the other birds stop singing and fly for cover, the deer lift their heads and stop moving and the rabbits run into the bushes. Suddenly, the forest becomes silent.

    When humans walk through the woods in a hurry or while talking with a friend, we don't see much wildlife. We may think that there aren't many animals living there, but more likely, they know we are coming and hide minutes before our arrival. But if we learn to avoid setting off alarms, we can see many more wild animals without frightening them. To practice, find a place in a park and sit quietly for an hour. Take note as the birds begin to relax and sing again. When I do this, I am always surprised at the wonderful thing animals will do when humans simply stay still long enough.

    Hip-hop culture covers many fields; it includes spoken words, break-dancing, beat-making, painting, fashion, lively design, technology, and more. Hip-hop is becoming the unofficial music in the education world, as more artists launch school programs, summer camps, and other activities connected city youth in the classroom through the beliefs of hip-hop culture. Even more and more university teachers — who once would have been strongly against hip-hop — have joined the crew. In the past two decades, hip-hop culture, including hip-hop education, has become a legitimate(合法的) field of study in universities and the subject of numerous books.

    Hip-hop culture has influenced every piece of American and global culture because the culture is so prevalent. Teachers must be willing to engage in it if it's part of the unique reality of their students' lives. That way, teachers can truly be effective, reaching students in a meaningful, culturally connected way.

    Teachers might at first feel frightened by hip-hop culture, an area in which they might not have previous knowledge or experience. But a lack of knowledge is actually a blessing; the best trained hip-hop educators have been those that are at the beginning disconnected(分离的) from the culture. One of the biggest sayings in hip-hop is “keep it real”. If a teacher comes to the classroom and says, “I don't know hip-hop, but I recognize that it's your culture and I want to learn,” the kids will teach the teacher, and then the students will be more willing to learn from that educator. Hip-hop is about a respect for youth culture.

    Humans were designed to stand upright. And yet in this modern world, too many of us spend our days with our heads lowered for a simple reason: we're staring at the tiny screen of a smart phone.

    People spend an average of 2 to 4 hours each day with their neck bent while shooting off emails or texts. That's 700 to 1,400 hours a year. The success of social media has led to a rapid development of bad smart phone posture(姿势).

    The average adult head weighs 10 to 12 pounds when it's in the upright position. However, because of the gravity, bending your head at a 15 degree puts 27 pounds of pressure on your spine(脊椎); a 30 degree neck bend could equal 40 pounds of pressure; a 45 degree bend adds the force of 49 pounds, according to the research from Dr. Kenneth Hansraj from New York. These stresses may lead to many problems.

    It's no secret that correct posture is better for your back. According to the researchers, good posture is described as ears aligned(成一条直线) with the shoulders. In proper alignment, spinal stress disappeared. It is the best position for the spine. Standing tall doesn't just make you look better; it improves your health, too. Other studies have found good posture has even been connected to ways of behaving. People who have poorer posture often have poorer physical and emotional health.

    The researchers describe bad posture as “the head in a forward position and the shoulders dropping forward in a rounded position”. Bad posture has been connected to many medical problems, including headaches and other problems, depression and heart disease. This is why Hansraj said it's important to be mindful of your smart phone posture. Though it is nearly impossible to avoid the technologies that cause these problems, people should make an effort to look at their phones with a correct posture.

Learning, Fast and Deep

    Over the past five years researchers in artificial intelligence have become the rock stars of the technology world. A branch of AI known as deep learning, which uses neural(神经的) networks to scan through large volumes of data looking for patterns, has proven so useful that skilled practitioners can command high six-figure salaries to build software for Amazon, Apple, Facebook and Google.

    The standard route into these jobs has been a PhD in computer science from one of America's top universities. Earning one takes years and requires a personality suited to academia, which is rare among more normal folk.

    That is changing.

    Last month fast.ai, a non-profit education organization based in San Francisco, kicked off the third year of its course in deep learning. Since its foundation it has attracted more than 100, 000 students around the globe from India to Nigeria. The course and others like it, come with a simple idea: there is no need to spend years obtaining a PhD in order to practise deep learning. Creating software that learns can be taught as a craft, not as a high intellectual pursuit to be undertaken only in an ivory tower. Fast. ai's course can be completed in just seven weeks.

    To make it accessible to anyone who wants to learn how to build AI software is the aim of Jeremy Howard, who founded fast.ai with Rachel Thomas, a mathematician. He says school mathematics is sufficient. "No. Greek. Letters," Mr. Howard intones, pounding the table with his fist for punctuation.

    Some experts worry that this will serve only to create a flood of unreliable AI systems which will be useless at best and dangerous at worst. In the earliest days of the Internet, only a select few nerds, namely computer holies with specific skills, could build applications. Not many people used them. Then the invention of the World Wide Web led to an explosion of web pages, both good and bad. But it was only by opening up to all that the Internet gave birth to online shopping, instant global communications and search. If Mr. Howard and others have their way, making the development of AI software easier will bring forth a new crop of fruit of a different kind.

    A man went into a restaurant and sat down at a table. He ordered the most expensive dishes. The waiter served the meal. He ate it with great joy. Then a small boy came in and sat at his table.

    The waiter came up and said to the man, "What would your little boy like, sir?"

    "Oh, just an ice cream," the man told him. Then he stood up and said to the waiter, "I'm just going out to buy a newspaper."

    He left the restaurant. The waiter gave the boy an ice cream. The boy took it and then stood up and walked to the door. The waiter ran towards him.

    "Excuse me," he said, "But your father hasn't come back and he hasn't paid for his meal or for your ice cream."

    "He's not my father," the boy said. "I don't know him at all."

    The waiter was puzzled. "What do you mean?" he asked.

    "The man came up to me in the street," the boy said, "He asked me if I liked an ice cream. I told him I did. Then he told me to come into the restaurant at 2 o'clock and sat down at his table. He said he'd give me one."