Winslow Homer was a famous American painter. Since Art History class in college, I had always admired his works and I was lucky to see a large exhibition of his works when I was in my early 30s.It was at this event that I bought a print of his painting, “Snap the Whip”. It always hung in my classroom until I retired from teaching.

    I thought it truly captured the freedom and fun of childhood. In the painting, a group of young boys are playing a game arm in arm on grass ground in front of a farm house. They are jumping and laughing wildly with great joy. One of the boys is falling down to the ground. They are not even wearing shoes!

    During my last year of teaching, there was a young woman in her first year of teaching right next door to me and we got to be good friends. She had been an art student before taking up education. Her eyes were drawn immediately to this print when she entered my room. So on my last day of teaching, after the students had left, I took the painting off the wall and walked next door and gave it to her.

    She was really surprised, but very glad to have it. I was delighted that she liked it and all the students she would have would treasure it as much as I had. We found the perfect place for it on one of her walls and hung it together. I was happy that she brought back this wonderful memory for me.

    Maybe you have ever seen a cross. A cross can be a piece of jewelry or an image in a painting. But do you know the cross is a very popular symbol for Christmas？

    It came from the story of Jesus' death on the cross two thousand years ago in Jerusalem. Jesus was Jewish，and at that time Jewish people were under Roman rule. Jesus was badly punished because he declared to be the Son of God and the King of Jews. Surely，the Son of God could have saved himself from the death！But the Bible says that Jesus had a reason to die that day. It was in God's purpose that it would happen.

    Christians call the day that Jesus died “Good Friday”. At first，it is hard to understand how a terrible day could ever be called good. Well，the story does not end there. Jesus died and he was buried. But three days later，Jesus was alive，and the whole world was changed.

    Today，Christians everywhere remember this important time. They celebrate Easter. Easter is the day that Jesus rose from the dead. After his death on the cross，Jesus' body was placed in a tomb. On the third day from then，God raised him from the dead. Jesus stayed on earth physically for several weeks. Many people saw him. Easter is the happiest time of year for Christians because they believe that Jesus had victory over death and evil and that now he lives with God the Father in heaven. But before celebrating Easter, Good Friday should be remembered. Jesus died a horrible and painful death. He suffered, though he did nothing wrong. Christian believe that Jesus was God's substitute(代表) for humans， because humans all do wrong. He died because of humans and he died for humans.

    Christians often wear crossed around their necks of hang them in their homes because they believe it is a very important sign. The cross helps them remember how much God loves them. It helps them remember how much his Son had to suffer. Seeing a cross always makes them think of Jesus' death， and what it means.

    CHICAGO(Reuters)－Smoking not only can wrinkle (皱纹) the face and turn it yellow—it can do the same to the whole body, researchers reported on Monday.

    The study, published in the Archives of Dermatology, shows that smoking affects the skin all over the body－even skin protected from the sun.

    "We examined non-facial skin that was protected from the sun, and found that the total number of packs of cigarette smoked per day and the total years a person has smoked were linked with the amount of skin damage a person experienced," Dr. Yolanda, who led the study, said in a statement.

    "In participants older than 65 years, smokers had significantly more wrinkling than nonsmokers. Similar findings were seen in participants aged 45 to 65 years." Yolanda's team added in their report.

    The researchers tested 82 people, smokers and nonsmokers, taking pictures of the inner right arms. They ranged, in age from 22 to 91 and half were smokers. Independent judges decided how wrinkled each person's skin was.

    When skin is exposed to sunlight, especially the face, it becomes coarse(粗糙的), wrinkled and discolored with a pale yellow color, Yolanda's team wrote.

    Several previous studies have found that cigarette smoking led to premature(过早的)skin aging as measured by facial wrinkles, the study said, but little has been done to measure the aging of skin not exposed to light.

    The previous research has found that cigarette smoke, among other things, causes blood vessels(血管)beneath the skin to constrict(紧缩), reducing blood supply to the skin.

    Smoking can also damage the connective tissue(组织)that supports both die skin and the internal organs (器官).

    Ever since mobile phones became widely used around the world, there have been concerns about how safe they are. All mobile phones give off a small amount of radiation when in use, which many believe could be a cause of cancer. However, two recently published studies tried to finally answer the question of whether using mobile phones actually brings a dangerous risk to humans.

    Carried out by the US government, the studies exposed rats and mice to radiation over the course of two years. A small number of the rats were found to have developed heart tumors (肿瘤) as a direct result of the radiation exposure. However, John Bucher, one of the study's authors, said that the animals were exposed to far more radiation than even the heaviest mobile phone user would usually be, reported The New York Times. Bucher also added that the findings didn't make him want to change his or his family's mobile phone usage habits.

    Indeed, the US Food and Drug Administration said it believes that it has “not found enough evidence that there are negative health effects on humans” from mobile phone use. Although mobile phones do give off radiation, it's a different type of radiation than that given off by dangerous sources.

    High-energy radiation – such as that given off by nuclear waste – is known to be very dangerous to humans as it is able to damage our DNA, leading to cancer or even death. On the other hand, low-energy radiation – such as the one given off by mobile phones – is considered to be harmless.

    We're exposed to this all the time, as it's given off by everyday objects like WiFi routers (路由器), televisions, and even bananas. Some argue that when it comes to human health, however, you can't be more concerned, even if the risk is only small. For those people, an earphone is advised when they are making phone calls and the time spent using mobile phones can be limited.

    But don't worry: there's no need to take bananas off the menu.

    Four years ago your friends congratulated you and your father talked big continuously. Four years ago you walked among the gothic towers and weathered traditions that sew our community together. But what's next, will I make friends, or I will measure up? And maybe you quietly wondered why a place like Yale, a place that sparked the drive of presidents, a place that raised the world-famous scholars, a place that trained Pulitzer Prize winners, would ever want you? I hope you had these questions because otherwise I might have embarrassed myself. I admit I asked all of these and more.

    I took an unconventional path to Yale. Five years ago I was working the evening shift at a clothing store in the suburbs of Virginia. My family had moved every year for the past five years and our finances were so consumed that retirement was not a possibility. Worse yet, my son was a junior at an Ivy League college in New Jersey and hearing about his privileged friends often reminded me of all the things I wanted to give him but couldn't.

    When I told him this he relied, “If you really want to spoil me, spoil yourself. ”Then he took my hands and told me I had a brilliant mind and deserved better than everything I had ever known.

    That summer I started community college while working full-time. Education was my second chance. I awoke my curiosity, vitality( 活力) and dignity that I never knew I could feel. When I read Eliot, Miller and Morrison, it was as if I were the first person to have ever read them, as if they were secret insights into the human soul and situations and I knew I couldn't stop.

    Walking among these gothic towers, among these traditions, and among this brilliant, vibrant and unapologetically eclectic Class of 2014 has been inspiring. Whether debating issues in class, or chatting over coffee, I have enjoyed, learned and loved every moment I have shared with you. You have made me a better person and I only hoped I have helped in some way to do the same for you.

    And yet even now this is dreamlike. Four years ago I was convinced no one would want me, I wouldn't measure up and as far as knowing what was next, I supposed I had resigned myself to more of the same. But I've come to learn that nothing great can really be accomplished without a healthy dose of terror. No one ever wrote epic(史诗般的) poems, built monuments or told bedtime stories about people who played it safe.

    I was terrified when I came to Yale. A big part of me thought I wasn't good enough. But a big part of life is ignoring the naysayers(反对者) especially the one inside you. Most people are stopped from doing great things by no one but themselves. I learned to tell myself to shut up. Sometimes in the mirror in the morning and others times in the dark before I went to bed. I came to realize once I could overcome my own fear I could overcome just about anything. If you haven't felt this yet I recommended it: it's the greatest joy you'll ever know.

    You've likely all met your own fear and misgivings(担忧、害怕). I charge you to tell that voice to shut up when necessary because in the end your greatness will not be about IQ but about the sincerity of your ambitions, the toughness of your character and your unwillingness to compromise in the face of difficulty, fear and uncertainty.

    And should someone tell you that it can't be done, or you're not good enough or it's not worth the trouble? Should others ask you to take the safe route, or stick to the path of least resistance? Should people say it's too late or your dreams are impractical? Look them in the eye, laugh a little and let them know “Nothing is impossible”.

    The year of 2017 marked the 100th birthday of the honoring Chinese-American architect Ieoh Ming Pei.

    From museums to business headquarters, Pei had designed many notable buildings around the world throughout his long professional career. According to the organizers of ''Rethinking Pei: A Centenary Symposium (百年纪念座谈会)" held that year, Pei remained one of the most celebrated architects of the 20th and early 21st centuries.

    The Hong Kong Bank of China Tower is one of his most famous works in Asia. As the bank itself also celebrated its centenary in 2017, it's worth examining the building's historical and architectural background to gain a deeper understanding of the architect who changed Hong Kong's skyline forever.

    The Bank of China Tower (BOC Tower) was completed in 1989, a year which the "New York Times" called, the year of I.M. Pei." For it was in this same year that Pei also completed the glass pyramid of the Louvre Museum in Paris, the Meyerson Symphony Center in Dallas, the Creative Artist Agency Headquarters in Los Angeles, and other marvellous architectures all around the world.

    Pei was commissioned (委托)in 1982 by the Beijing-based Bank of China to design it shead quarters in Hong Kong, but construction did not start until 1985.

    There were many reasons for the delay. One of the biggest was the huge challenges posed by the location. The land parcel had been the address of a Victorian building which served as a prison during Japanese occupation of Hong Kong between 1941 and 1945. This terrible heritage might be one of the reasons why it was dismantled in 1982.

    For I.M. Pei, the challenge of the site was not its past, but its present: the relatively small land parcel was surrounded on three sides by elevated roadways serving high-speed heavy traffic, meaning there was no possible public pedestrian access. Then there was its awkward trapezoidal (梯形)shape and the fact that the site also had a deep north-south height difference.

    Another challenge was the unavoidable comparison of the BOC Tower to the neighboring Hong Kong and Shanghai Bank Headquarters(HSBC), which was also under construction. A spectacular building generously funded, its architect Norman Foster was simply told to create "the best bank building in the world." At that time it was also the world's most expensive building, costing $668 million. The Bank of China Tower's budget was approximately one fifth of the budget allowed by HSBC.

    The Hong Kong government had promised HSBC that no tall buildings would ever be built in front of its headquarters. Besides, in between the site of the Bank of China and the harbor, there were already a few buildings over 70 meters tall blocking views.

    Recognizing that going tall was the only way to create a landmark at this site with his budget, Pei came up with an architectural tower design that was simple, expressive, innovative, and upon its completion, the tallest building outside of America and the fourth tallest in the world.

    After the Bank of China officially moved into the tower in 1991, noted architect and critic Peter Blake visited the building and declared it to be "probably the most innovative skyscraper structure built anywhere to date."

    Now 30 years after the building^'s construction, the Bank of China Tower continues to offer valuable lessons of architectural and structural creativity under the most demanding conditions. Most importantly, the tower has become one of the most important cultural icons for the city of Hong Kong.