Philadelphia, Pennsylvania w America's fifth largest city. Once a major American colonial city, it is the home of America's first library, its first hospital, and its first zoo. Now it is also the first US city to be named a World Heritage City. On November 6, 2015. Philadelphia joined more than 260 other cities that have been recognized for their influence on the world. These cities include Paris, France Florence, Italy and Cairo Egypt.

    "Today marks the start of a new and exciting chapter in the history of Philadelphia" remarked Philadelphia Mayor Michael Nutter when the announcement was made. “As a World Heritage City. Philadelphia is being officially recognized on the global stage for its wealth of contributions to the world. ”

    To be named a World Heritage City, a city be home to a UNESCO World Heritage site are selected for their universal value and significance. For Philadelphia, the site is Independence Hall.

    Independence Hall is where two of the most important documents, approved in US history - the Declaration of Independence and the US Constitution-were adopted. The Declaration of Independence, approved on July 4 1776, united the 13 former British colonies and declared them independent from British rule. The US constitution, signed in 1787, established the American democratic system of government. Democracy is a system of government in which the people elect their leaders. The Constitution later spelled out basic freedoms American citizens have.

    Philadelphia Deputy Mayor Alan Greenberger says the city's selection as a World Heritage City also reflects ta its educational, cultural, and economic achievements. The city is home to dozens of colleges and universities, and many museums, such as the Philadelphia Museum of Art.“Philadelphia has rightfully earned its place as one of the greatest cities in the world.” Greenberger says.

    One recent night, while I was leafing through its pages of an old journal, my eyes met a quote by the British writer Graham Greene that I had marked. “A prejudice had something in common with an ideal.” In other words, ideals general descriptions of people's expectations of themselves and others can often lead us to unreasonable ideas. It got me thinking about how we often allow ourselves to generalize about groups of people. We like to stereotype people by the color of their skin, the year of their birth or any other related factors.

    I grew up in a multi-racial corner of America. The different groups were often subject to narrow stereotypes: Jewish people were “greedy,” Mexicans were “poorly educated,” and Asians were “good at math.” These labels were taught to us from a young age. They wormed their way into our belief systems, harming how we came to see others. It made me sad growing up to see people repeat these stereotypes as if they were true. The rush-to-judgment of people breeds a culture of discrimination (歧视).

    You can also see these over-generalized description being made against today's Chinese people. Whether it be a lack of interest or worry among millennials (千禧一代) being described as “monkish,” or “dad-fashion (复古作风)” which has given the “greasy middle-aged men” tag, stereotypes always seem to gain a foothold in the consciousness of our society. But these generalizations do real harm as these myths may become part of the wider population.

    It's about time that we, as a society, walked away from generalizations and stereotypes. I leave you with the words of Martin Luther King Jr. from his famous “I Have a Dream” speech: “I look to a day when people will not be judged by the color of their skin, but by the content of their character.” By reserving judgment and really getting to know the individual, you might just find your irrational ideas have no foundation.

    I was waiting for my train and on the subway station's floor was a man just sitting there. I looked around and nobody stopped so I just went my way. After a few steps, I turned and asked him whether he needed help. He told me his house was one station further and he would only need to take the train there. So I reached for his hand to help him stand up.

    He wanted to take the stairs but I feared that he would hurt himself since he seemed too weak to walk, so I asked him to take the elevator. Even though my mind was trying to turn the danger lights on, I put the thought that I should not go alone with a drunken man out of my mind and accompanied him on the elevator.

    We arrived on the platform with no incidents. The man's knees seemed to soften, so I asked him to rest on a bench. While sitting there, he thanked me, telling me that I saved him. No, I said, I really did nothing; he saved himself as he walked on his own feet.

    At the next station, we said our goodbyes. Before I knew it, he left 100 dollars and dashed out of the train. There was no way to give him back his money. I wanted to leave it on the seat, but a young woman who thought it belonged to me ran after me and gave me the note.

    My initial reaction to getting that money was of shame and I even felt offended. Then I thought he just wanted to thank me, the best way he knew how. Now, my question is — what act of kindness shall I do with these 100 dollars?

    No. 1 Snapchat

    With this app, the pictures people share with friends will disappear automatically(自动地) after they are seen. Snapchat has become more and more popular since 2012. Over 700 million photos have been shown daily by May 2014, up from 20 million per day in 2012.

    No. 2 Uber

    The on-demand car service app allows users to order a ride and get picked up within minutes. On-demand service means no need to reserve (预订) and no waiting in taxi queues. And the app can be used in more than 40 countries.

    No. 3 WhatsApp

    WhatsApp became the world's most popular chat app in 2014 with over 600 million monthly users in August. It was also bought by Facebook in October for about $ 22 billion (about 136 billion yuan).

    No. 4 Venmo

    The mobile payment service is used to share bills by friends, who get together to have dinner or do something else. It took Millennials' (生于1984-1995年间的"千禧一代") smart-phones by storm in 2014. It is said that among college students the word "Venmo" is now being used as a verb—"just Venmo me".

    With the New Year weeks approaching, you're looking forward to watching the splendid fireworks shows that will welcome 2019 worldwide. Unfortunately, visually impaired and blind people can't experience this joyful celebration. That may change soon thanks to Feeling Fireworks, a fireworks experience invented by the Disney Research Lab in Switzerland.

    To experience the show, users stand before a large flexible screen, place their hands at the base of the screen and move them around to feel the fireworks. Alternatively, their hands can be situated in the center of the screen, where the initial explosions happen, and then moved across to explore other fireworks.

    As the fireworks begin to explode, five nozzles (喷嘴) at the back of the screen start to shoot water, creating movement of water imitating the show. One specializes in the "blooming flower effect", another reproduces the "crackle" effect, and the rest take care of rockets and explosions. A computer controls the timing, and Feeling Fireworks allows users to experience fireworks similar to those in the sky.

    Paul Beardsley, who led the research team, says, "We want blind, visually impaired, and sighted people to all try Feeling Fireworks, and to have a shared and enjoyable memory of a fireworks evening." And the screen displaying the vivid images created by water makes it fun for everyone.

    The low-cost technology is still in its early stage, with only a 66 percent success rate. However, the team plans to continue improving the experience and believes the day when everyone will be able to enjoy the thrill of fireworks shows is not far. When ready, Feeling Fireworks will initially be available only at the Disney theme parks, and then hopefully, at fireworks shows worldwide.

    Earthquakes strike suddenly at any time of the day or night, but there's no way to tell when. If an earthquake happens, it may cause many deaths, injuries and damage. So you need a good preparation ahead of time. Decide how and where your family will get together if separated. Choose an out­of­state friend or relative that the family members can call after the quake to report where they are and how they are. Know the safe places in each room: under the strong tables, desks, or against inside walls. Keep enough food, water and other things, including a flashlight, a radio, medicines and clothing.

    During the earthquake, you should keep a clear head and never be too nervous to know what to do. Protect your head and neck with your arms. If possible, take a book, a pillow or any other things to protect yourself from falling glass and ruins. If you are indoors, you must immediately lie under any strong furniture. If outdoors, move to an open area away from trees, buildings, walls or powerpoles. If you are in a narrow valley, move to the centre of it and look up for falling stones. If you are in a car, move to the side of the road and stop the car. Do not stop near buildings, power lines or on or under bridges. Stay in your car until the shaking stops.

    Do not move a badly injured person unless he is in great danger after the earthquake. Do not use the telephone immediately unless there is a serious injury or fire. Turn on your radio for instructions and news reports. Be prepared for aftershocks. If you want to leave your home, post a message inside your home telling your family members where you can be found.