When I looked at the grade on my math paper my jaw (下巴) almost dropped to the ground: a big “65” in bright red ink. I had never received such a terrible grade before.

    I was so ashamed that when I got home that afternoon I lied to my dad. I told him I got 85 and that the report wouldn't come until the end of the month. Dad smiled. His daughter would never lie about her grade, so he didn't doubt the unusual delay (延迟) of my report.

    A month later, Dad casually (随意地) asked me again about the report at the dinner table. He looked right into my eyes and asked for an answer. Having no choice. I told him that I had in fact got just 65 in my math final. I had lied because I didn't want to let him down.

    For a moment, he just looked at me. I would have preferred a telling off (斥责) than that silence. Finally, Dad said, m a hurt voice, “You have already let me down, with your lie. I am not disappointed at your math score. That is no big deal-on one can be perfect all the time. But I am very disappointed in you. If you can't be honest with your dad. who can you be honest with? It's much easier to achieve a better grade than rebuild someone else's trust in you.”

    Dad's words touched my heart. I couldn't forgive (原谅) myself for having hurt his feelings I took out the report that I had been hiding for weeks, handed to him and apologized, sincerely I realized that my honesty is not only important to me personally, but to those around me that truly care .about my well-being (幸福).

    In one of Shakespeare's plays a character says: “No legacy (遗产) is so rich as honesty.” After the crisis between Dad and me, I began to understand those words.

    It was the day after Halloween when my grandmother was admitted to the hospital with the worst headache she'd ever had. While posing in our costumes the night before, we knew something was wrong, just not how wrong.

    Grandma's house was the central gathering place of my family. Sunday lunches, birthday dinners, Easter, Thanksgiving, and Christmas — all were our traditions, with her as hostess. While my parents were busy running their small business, there were many nights when Grandma fed me and put me to bed in her spare room, until they came to get me. I spent my summers at Grandma's and I went everywhere with her. I couldn't imagine a time when she wouldn't be around me.

    Then November 1,1991 began her month-long stay in the hospital—she suffered from a rare infection (感染)called nocardia asteroides. After being born in the year of the Great Depression, living through World War II, raising three kids, and being widowed at the age of 48, Grandma never expected to live into her seventies. The infection in her brain seemed to confirm that she wasn't long for this world. But that's not the end of her story. A team of doctors successfully removed the abscess(脓肿), and Grandma even made it into a local medical journal. Her doctor called her “the brain lady”.

    Grandma celebrated her 85th birthday in March this year. In the almost 23 years since her recovery, she's seen two of her four grandchildren get married and welcomed three great-grandsons. Although they damage something in her house, she loves it when my two boys come over. And while I know they make her day, seeing her love blossom for another generation makes my day too. Happy Grandparents' Day to my amazing grandmother!

    There's a new frontier in 3D printing that's beginning to come into focus: food. Recent development has made possible machines that print, cook, and serve foods on a mass scale. And the industry isn't stopping there.

     Food production

    With a 3D printer, a cook can print complicated chocolate sculptures and beautiful pieces for decoration on a wedding cake. Not everybody can do that — it takes years of experience, but a printer makes it easy. A restaurant in Spain uses a Foodini to "re-create forms and pieces" of food that are "exactly the same," freeing cooks to complete other tasks. In another restaurant, all of the dishes and desserts it serves are 3D-printed, rather than farm to table.

    Sustainability(可持续性)

    The global population is expected to grow to 9.6 billion by 2050, and some analysts estimate that food production will need to be raised by 50 percent to maintain current levels. Sustainability is becoming a necessity. 3D food printing could probably contribute to the solution. Some experts believe printers could use hydrocolloids (水解胶体) from plentiful renewables like algae(藻类) and grass to replace the familiar ingredients(烹饪原料). 3D printing can reduce fuel use and emissions. Grocery stores of the future might stock "food" that lasts years on end, freeing up shelf space and reducing transportation and storage requirements.

    Nutrition

    Future 3D food printers could make processed food healthier. Hod Lipson, a professor at Columbia University, said, "Food printing could allow consumers to print food with customized nutritional content, like vitamins. So instead of eating a piece of yesterday's bread from the supermarket, you'd eat something baked just for you on demand."

    Challenges

    Despite recent advancements in 3D food printing, the industry has many challenges to overcome. Currently, most ingredients must be changed to a paste(糊状物) before a printer can use them, and the printing process is quite time-consuming, because ingredients interact with each other in very complex ways. On top of that, most of the 3D food printers now are restricted to dry ingredients, because meat and milk products may easily go bad. Some experts are skeptical about 3D food printers, believing they are better suited for fast food restaurants than homes and high-end restaurants.

    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."

    Fourth-grade teacher Tori Nelson allowed one of her students to shave her head in the schoolyard, after bullies（仗势欺人者） teased him about his own buzz cut. Ms. Nelson got the idea after noticing that Matthew Finney, a shy boy from her homeroom at Winlock Miller Elementary School in Washington State, was standing outside his classroom crying and wearing a winter hat.

    Ms. Nelson could see the back of his neck had been shaved, and since Matthew usually had very thick curly brown hair, she realized that he'd had a haircut over the weekend. She asked him what was wrong， and he said he'd gotten a buzz cut for the summer. But this morning, a fifth grader on the bus made fun of him, and he didn't want to come to class and get laughed at by other kids. Ms. Nelson tried to convince Matthew to come inside, but since school rules banned kids from wearing hats indoors he refused—explaining that he was afraid of showing his haircut to the other children in case they also made fun of him.

    "Finally I said, 'If you take your hat off and come to class, I'll let you give me a buzz cut too,' Ms. Nelson told Yahoo Parenting." I figured it's just hair, and mine is already short anyway. I might as well get it shorter in time for the warm weather.

    Matthew excitedly took her up on the offer, and Ms Nelson and another teacher gathered all the fourth graders together during break time. A school employee brought in scissors, which Matthew used to the cheers of his classmates, excitedly watching as their teacher's hair fell away onto the ground in the schoolyard.

    "It was a lot of fun for the kids, and it helped Matthew feel better about himself." said Ms Nelson." You have to do what it takes to reach children. Teaching isn't just about reading and writing: it's about self-worth and accepting differences.

    Losing a wallet is one of those careless acts most of us have come across, at some point or the other in our lives. While most of us tend to move on after mourning over the lost necessities, there are a few lucky ones who get them back, with the help of the police or the generosity of the person who finds it.

    And then there is Hunter Shamatt, who not only got back his wallet but with some added happiness that was tagged along!

    Hunter was on his way to attend his sister's wedding on a Las Vegas-bound flight when he realized that he has misplaced his wallet, sometime during the journey. Hunter's family reached out to the Frontier flight to enquire if someone had handed it over to them. Unfortunately, there was no sign of the missing wallet.

    But wait. The story was far from over. Just a week after Hunter's sister's wedding, he received a package in his mail. And guess what? There was his wallet! Surprisingly, the wallet was not the only thing that was inside the package. It also had a handwritten note for Hunter which turned out to be a bonus! The piece of paper read,

"Hunter, Found this on a Frontier flight from Omaha to Denver — row 12, seat F wedged between the seat and wall. Thought you might want it back. All the best.

P.S. I rounded your cash up to an even $100, so you could celebrate getting your wallet back. HAVE FUN!!!"

    Moved by the touching gesture, Hunter's mom, Jeannie Shamatt, decided to write a post on Facebook giving a detailed description of the incident. She also urged everyone to share the post as she would like to meet and greet the person behind the act of kindness, personally.

    Now, thanks to the astonishing power of social media, the post finally reached the man behind the note. The man was identified as Todd Brown and it was one of his co-workers who made sure Jeannie Shamatt's post reaches his colleague. Jeannie turned to Facebook again to thank Brown and his family for restoring her faith in humanity.

    "I try to teach my children to do the right things in life, help people when you can regardless of the outcome. This story is more about restoring faith in people than anything. We hear a lot of bad news but not enough good news. I personally want to thank Todd Brown and his wife for restoring faith that there are amazing people out there."