Every day when Glen Oliver orders his morning coffee at the drive-through window of a local cafe, he insists on paying for the order of the person behind him. He also asks the restaurant workers to tell the customer to have a great day, in case they're not already having one.

    Oliver has never made a big deal out of his own generous actions until a letter was published by a news website in November. He found out that he had not just bought someone his breakfast —he had saved a life.

    According to the website, someone had written a letter stating that on July 18th, he was planning on committing suicide. The writer said that while he was at the drive-through window, he was planning on going home, writing a note and ending his life. When he went to pay for his coffee and muffin, however, the cashier told him that the man in the SUV in front of him had picked up the tab and told him to have a great day.

    “I wondered why someone would buy coffee for a stranger for no reason,” said the writer. “Why me? Why today? If I were a religious man, I would take this as a sign. This random act of kindness was directed at me on this day for a purpose.”

    When the writer arrived home, he couldn't hold back his tears and started to think about the simple good deed that had affected him so deeply. “I decided at that moment to change my plans for the day and do something nice for someone. I ended up helping a neighbor take groceries out of her car and into the house.”

    The writer says that in the months following that fateful event, he does at least one kind thing for others every day. “To the nice man in the SUV, thank you from the bottom of my heart. Please know your kind gesture has truly saved a life,” he said. “On July 18, 2017, I had the greatest day.”

    Imagine you're standing in line to buy a snack at a store. You step up to the counter and the cashier scans your food. Next, you have to pay. But instead of scanning a QR Code(二维码) with your smart phone, you just hold out your hand so the cashier can scan your fingerprint. Or, a camera scans your face, your eyes or even your ear.

    Now, this type of technology might not be far away. As technology companies move away from the traditional password, biometric (生物特征识别的) security, which includes fingerprint, face and voice ID, is becoming increasingly popular.

    In 2013, Apple introduced the iPhone 5s, one of the first smart phones with a fingerprint scanner. Since then, using one's fingerprint to unlock a phone and make mobile payments has become a commonplace, bringing convenience to our lives. And since 2016, Samsung has featured eye-scanning technology in its top smart phones, while Apple's new iphone X can even scan a user's face. But despite its popularity, experts warn that biometrics might not be as secure as we imagine." Biometrics is ideally good in practice, not so much," said John Michener, a biometrics expert.

    When introducing the new iPhone's face ID feature, Phil Schiller, Apple's senior vice-president, said. "The chance that a random person in the population could look at your iPhones X and unlock it with their face is about one in a million." But it's already been done. In a video posted on a community website Reddit, two brothers showed how they were each able to unlock the same iPhone X using their own face. And they aren't even twins.

    "We may expect too much from biometrics," Anil Jain, a computer science professor at Michigan State University, told CBS News. "No security systems are perfect."

    Earlier last year, Jain found a way to trick biometric security. Using a printed copy of a thumbprint, she was able to unlock a dead person's smart phone for the police, according to a tech website Splinter. "It's good to see biometrics being used more," Jain told CBS News, "because it adds another factor for security. But using multiple security measures is the best defense."

    China's government has been trying all measures to reduce pollution in the past few years. Now people can enjoy a fresh environment everywhere. The following two graphs are adopted from the column of “City Information” on the webpage of Beijing Review.

Graph 1: Olympic Cities Air Quality Report

Graph 2: Chinese National Standard

Notes:

    API stands for Air Pollution Index(指数).

    Particulate matter (PM10) is a major component of air pollution that threatens both our health and our environment. It consists of very small liquid and solid particles floating in the air.

    Sulfur dioxide(SO₂) acts as an acid. Inhalation(吸入) results in labored breathing, coughing, or a sore throat and may cause permanent lung damage.

    Sometimes people come into your life and you know at once that they were sure to be there. They serve some sort of on purpose, teach you a lesson or help find out who you are or who you want to become. You never know who these people may be: your classmate, neighbor, teacher, long-lost friend or even a real stranger. But you know that every moment they will affect your life in some serious way.

    Sometimes things happen to you. At the time they may seem terrible, painful and unfair. But later you realize that without getting over those difficulties you would have never realized your further ability and strength. Everything happens for a reason and nothing happens by chance or with good or bad luck.

    The people you meet affect your life, and the successes and failures(失败) you experience, create who you are. Even the bad experiences can be learned from. In fact, they are probably the most poignant and important ones.

    Enjoy every day even every moment and take from it everything that you possibly can, for you may never be able to experience it again. Talk to people you have never talked to before, and really listen. You should set your sights high, hold your head up, tell yourself you are a great one and believe in yourself.

    You can make your life anything you wish. Create your own life and then go out and live it.

    A day in the life of 18-year-old David Lanster is full of teenage activities: school, baseball practice, homework. And then he starts cooking. "Some nights I'm up until 1 a.m. making pies, or even later if we're cooking beef," said the student at Ransom Everglades High School in Florida, US.

    For the past year, Lanster and Kelly Moran, his classmate, have been hosting fancy dinner parties at Lanster's parents' home. Their meals have 17 courses and are all made by them. Their guests used to give them gifts to thank them, until the pair decided to do something nice for charity. "We got some really great Miami Heat tickets, a nice watch, and many kitchen machines," Lanster said. "But we wanted to make this something positive for people rather than us."

    Lanster and Moran focused on Common Threads, a charity(慈善机构) that helps to teach kids in poor neighborhood to cook and make healthy eating choices. The young cooks ask their guests to give however much they want as payment for their meals. It all goes to Common Threads because Lanster's parents cover their food costs. After their last 12-person event, Lanster and Moran gave $1,600 to the charity. Now, they're taking their show out of the kitchen and on the road. Lanster and Moran have started to organize private dinner parties in a similar way: the host pays for the ingredients(食材), and the guests make a donation (捐赠) to a charity.

    Outside the kitchen, the two are busy preparing their college applications. Neither is sure what they will do in the future, but they've promised their parents that they'll leave cooking alone until they finish high school.

    Ahead of the summer travel season, airlines in the United States usually compete to sell tickets and fill seats. But the airlines that operate the grounded Boeing 737 Max planes have a new problem: there are not enough seats to meet the demand.

    The revenue(收益)is right in front of them. They can see it, but they can't meet it, said Mike Trevino. He is an airline industry expert for Southwest Airlines Pilots Association, The grounding of Boeing's 737 Max came after two deadly crashes in five months. Southwest Airlines is the world's largest 737 Max operator. The company has 34 of the planes.

    American Airlines operates the second-most, with 24. These planes have been removed from use until at least August, The grounding of the planes has led Southwest to cancel 160 of its 4,200 daily flights between June 8 and August 5.

    American Airlines will cancel 115 daily flights, or 1.5 percent of its total summer flights .Southwest only flies Boeing 737s. It had estimated $ 150 million in lost revenue between February and March 31--mostly because of MAX cancellations.

    The 737Max was grounded worldwide in March following a deadly Ethiopian Airlines crash. It came five months after a Lion Air crash in Indonesia. All on board both planes died.

    Boeing is under pressure to provide additional software. Experts are examining the original software as a possible reason for the crashes.

    Boeing must prove to worldwide regulators that the plane is safe to fly. That process may take more than 90 days. Planes in the United States are usually mostly full during the months of June, July and August.