I am 26. I'm clear that I'm never going to catch up with Mother Teresa. But I want to do something to help people every single day like her.

    Everybody thinks we just serve food and soda. The safety training is serious and stressful. Caring for 49 people in a business class in 90 minutes is not easy. I had a roommate who was a waitress; she just left a candle and a table cloth burning, and I used a fire extinguisher to put out the fire. If something goes bad at her job, she calls the police. But if something happens up in the air, it's up to us.

    I'm single and have no kids. I've flown every Christmas since 1995. If I fly, someone else can be with their kids. Christmas in an airport can be depressing, but it's the little things that make a difference.

We're not robots. It's hard to put on a smile and just pretend everything is great when it isn't. I've seen co-workers lose a family member the day before a trip and just pull themselves together (take control of their feelings and behave in a calm way). At the end of a 14-hour flight, it's like, "It was really nice to help you, but I'm ready for you to get off the plane." Those last 15 minutes can be the longest 15 minutes of your life. You can't wait to turn off the flight attendant's voice and get something to eat without anyone saying "Excuse me."

Sometimes I go all day and never hear a "please" or a "thank you" when you say "thank you", it's huge. It makes us feel like you actually see us as fellow humans. We're up there together at a height of 30,000 feet, enjoying the miracle of the modern flight.

    With the approval of the Singapore government, a company called nuTonomy has become the first-ever to test self-driving cars with the public. Interested people could sign up for a free trial run at no cost. When they received an invitation from the company, they could book a ride on the driverless taxi service from their smartphones.Not surprisingly,the rides proved very popular,with dozens of customers eagerly trying out the cars each day.

    Driverless cars are a great option for those who do not know how to drive and for those who do not enjoy driving.Some researchers even believe that such cars can make road travel safer by reducing human errors.But since driving requires many of our senses to be on alert（高度警觉）, replacing that by machines is easier said than done.

    The environment in which cars operate is constantly changing—from roads and pedestrians to co-travelers. A driverless car needs special equipment to analyze its surroundings. Then, it must translate that information into a practical route and safe travel. To be truly autonomous, a car has to do this independently without human input. Today, some cars have a certain degree of autonomous functions. But even the completely automated vehicles still require a driver to take back control under uncertain conditions.

    The island city-state is well known for excellent roads and drivers who obey the rules. This has made it ideal for real-world testing and feedback. The government has encouraged research in autonomous vehicles, since it can improve safety and potentially reduce the traffic burden as well.

    In 1996 John Jones made an unusual discovery. He had just enlarged (扩大) a piece of paper money for a friend—a Confederate bank note, money issued (发行) by banks in Southern States of America during the Civil War. When he was face to face with the picture, he couldn't believe his eyes: slaves (奴隶) happily picking cotton in their master's fields.

    Jones grew up in South Carolina. He had heard painful stories of slavery from his greatgrandmother. The picture on the money did not match (匹配) the history of African American slaves that he'd heard all his life. “I had never seen that type of picture on money before,” he said.

    Jones wondered why slaves looked so happy. He started doing research.

    Searching for and finding the answers to his questions changed his life. During two years' search, Jones found more than 120 different bills. He discovered that the bills had several things in common. They showed slaves working in jobs related to farming. Many of them showed healthy and smiling slaves at work. None of the bills showed the hardships of slavery.

    Jones wanted to share what he had learned. “I wanted other people to see what I had seen,” he said. He decided to make large paintings of the pictures on the money. After three years of work, Jones had painted more than 80 slavery scenes (场景).He paired each painting with the money on which the picture appeared. “The Color of Money”—an exhibit (展览) of his work—has toured the country.

    Jones' paintings tell an important story about the South 150 years ago. He likes to repeat the saying. “The story is on the money.” In this case, the saying happens to be true.

    Although English is not as old as Chinese, it is spoken by many people around the world every day. English speakers are always creating new words, and we are often able to know where most words come from.

    Sometimes, however, no one may really know where a word comes from. Did you ever think about why hamburgers are called hamburgers, especially when they are not made with ham? About a hundred years ago, some men went to America from Europe. They came from a big city in Germany called Hamburger. They did not speak good English, but they ate good food. When some Americans saw them eating round pieces of beef, they asked the Germans what it was. The Germans did not understand the question and answered. "We came from Hamburger." One of these Americans owned a restaurant, and had an idea. He cooked some round pieces of beef like those which the men from Hamburger ate. Then he put each between two pieces of bread and started selling them. Such bread came to be called "hamburgers". Today "hamburgers" are sold in many countries around the world.

    Whether this story is true or not, it is certainly is interesting. Knowing why any word has a certain meaning is interesting, too. The reason, for most English words, can be found in any large English dictionary.

    Until the 1990s coffee was rarely served in China except at luxury hotels aimed at foreigners. When Starbucks opened its first shop there in 1999, it was far from clear that the country's tea-drinkers would take to such a different and usually more costly source of caffeine. Starbucks tried to attract customers to coffee's bitter taste by promoting milk and sugar-heavy concoctions(调和) such as Frappuccinos.

    But coffee has become fashionable among the middle class in China. Starbucks now has about 3, 800 shops in China more than in any other country outside America. Statista, a business-intelligence portal(门户网站), says the roast coffee market in China is growing by more than10 %year. Starbucks and its rivals see big opportunities for expanding there.

    So too, however, do home-grown competitors. A major new presence is Luckin Coffee, Beijing- based chain. Since its founding less than two years ago, it has opened more than 2,300 shops. On May 17th Luckin's initial public offering on the Nasdaq stockmarket raised more than $570m, giving it a value of about $4bn.

    Luckin's remarkable growth is sign of change. No longer do Chinese consumers see coffee as such a luxury. Most of Luckin's shops are merely kiosks where busy white-collar workers pick up their drinks, having ordered them online. Super-fast delivery can also be arranged through the company's app. Independent coffee shops are springing up. The growth is striking considering the country's reputation for its tea-drinking culture where many residents like to relax in teahouses sipping tea served gracefully.

    But the two markets are different. The teahouses tend to cater to older people who like to spend long hours playing mahjong and gossiping. At the coffee shops it is rare to see anyone over 40. Young people use them for socialising, but much of their interaction is online -sharing photos of their drinks and of the coffee-making equipment. An option on the Chinese rating app Dianping allows users to search for wanghong ("internet viral") coffee houses.