Breakthroughs in science and technology are paving the way for modern cities to support bigger populations. Now, we see the most exciting urban innovations to show you exactly how they'll improve your city's infrastructure(基础设施).

Lighting Up The Night

    Anthony Di Mari dreamed up an electric tree to help irrigate public parks and light them at night. These electric trees contain a special infill (填充物) that collects water from rainfall. The water is then distributed through a shallow underground irrigation system with the help from the trees' swaying movement. An electric motor turns energy from the waving of the artificial trees into electricity, which is used to light up the trees' outer LEDs.

Thinking Outside The Box

    As more people flock to urban areas, city planners will need to get increasingly creative about how to satisfy residents' health and transportation needs within decreasing available space. One way to achieve this is by updating infrastructure to support biking and walking by building suspended(悬浮的) roundabouts like hovering in the Netherlands. By lifting bicycle and pedestrian traffic above busy roadways, cities can significantly decrease over-crowded traffic condition.

Waving Hello To Clean Energy

    Cities that don't receive enough sunlight may find an attractive alternative in wave power. Since ocean waves rarely experience disruption(中断), electric engines driven by their clockwork push-and-pull can reliably provide power throughout the year. Further, thanks to advances in wave power technology, engineers have been able to move wave power engines farther offshore, where the waves pack the most punch, making the engines extremely efficient. So in the future, heavily populated coastal cities may use wave to meet their energy needs.

    Dodder is an unusual and unwanted plant that attacks other plants. Except for its flowers, the plant looks like spaghetti, a kind of noodles in the shape of long thin pieces that look like string when they are cooked. It's almost leafless, thread-like stems (茎) hang down on top of other plants that dodder needs to stay alive. Dodder does not produce its own food. Instead, it steals food from other plants. It feeds by sucking juices from the plant which is wrapped around, often making its host very weak or even killing it.

    Dodder can find other plants by their smell. When a young dodder plant starts growing, it follows the smell of plants it prefers, like tomato plants, potato plants, or other farm crops. Unlike most plants that usually grow in the direction of light or warmth, a dodder plant will grow in the direction of, for example, tomato smell—if a tomato happens to be growing nearby.

    However, a young dodder plant must find a host plant quickly. It no longer needs its root once it is attached to the host and wrapped around it. If it cannot catch a smell of a potential host within a few days, it will dry up and disappear—even if there is plenty of water around. Once it finds a host, the young dodder plant will attach itself to it and start growing faster. At that point the dodder plant will drop its root.

    Dodder is thus a difficult weed to manage and a real headache for farmers. When it does get out of hand, dodder can greatly reduce a farmer's harvest or even destroy crops completely. Before sowing their produce, especially farmers in warm parts of the world often check to make sure no unwanted dodder seeds have mixed with their crop seeds. This is a good way to stop dodder plants from making their way to a crop field secretly.

From birth to death, the word kick has been given an important part in expressing human experience. The proud and happy mother feels the first signs of life kicking inside her body. And that same life——many years later—— comes to its end in a widely-used expression, to kick the bucket( 吊桶) . The expression to kick the bucket is almost 200 years old. One belief is that it started when an English stableman(马夫) killed himself by hanging while standing on a bucket. He put a rope around his neck and tied it to a beam(梁柱) in the ceiling, and then kicked the bucket away from under him.

    Another old expression that comes from England is to kick over the traces. Traces were the chains（链子） that held at horse or mule to a wagon(货运马车)or plow. Sometimes, an animal refused to obey and kicked over the traces.

    Kick around is an expression that is heard often in American English. A person who is kicked around is someone who is treated badly. Usually he is not really being kicked by somebody's foot. He is just not being treated with the respect that all of us want. A person who has kicked around for most of his life is someone who has spent his life moving from place to place. In this case, kicking around means moving often from one place to another. Kick around has another meaning when you use it with the word idea. When you kick around an idea, you are giving that idea some thought.

    There is no physical action when you kick a person upstairs, although the pain can be as strong .You kick a person upstairs by removing him from an important job and giving him a job that sounds more important, but really is not.

    Still another meaning of the word kick is to free oneself of a bad habit, such as smoking cigarettes. Health campaigns urge smokers to kick the habit.  

    As health care costs continue to rise, a growing number of companies are working out programs designed to keep their employees healthy.

    Thomas Chapple is the senior vice president. “It's really important to us because medical costs are going up like crazy, he says. This company spends more than 200 million a year on medical costs for its employees around the country. The best thing we have seen as a way to control the medical cost is individual fitness.”

    We have a fitness center, “Shawn Flaherty, director of public relations for Freddie Mac.,” says, “We have a health benefits plan that encourages people to work out three times a week, get cholesterol (胆固醇) checks, as well as 'not to smoke.' If they do that, it will cost them less for the health benefits.”

    Rachelle Clark works for Freddie Mac. “I feel great. You know the benefit is rewarding. I like to look good and feel healthy. I am just fortunate that I work for the company that provides some type of facility for the employees.”

    While on-site fitness centers are popular, some companies pay membership fees at local gyms for employees. The companies also offer classes such as boxing, yoga and dancing. Employees see those health programs as a valuable benefit.

    Tom Brook exercises five days a week. As a newspaper reporter he has a tight schedule, although Tom says it's not that difficult for him to make time for a workout. “It is great. It is right here where we work,” says Tom, “So everybody gets a chance to use it whenever they want to. I have lost weight and never been in better shape.”

    The programs may not be a magic cure for rising health costs, but they seem to have a positive impact on both employers and employees.

Located at Europe's biggest water park, the Galaxy Erding in South Germany, the world's first VR water slide takes the exciting experience to a whole new level by offering thrill-seekers the choice of three attractive worlds — Space, Sky, or Snow. By simply wearing a headset, riders can slide through a magical alien world, follow beautiful butterflies around floating islands or put themselves in a white winter wonderland. To make the experience even more heart-stopping, the 160-meter-long ride that lasts about 35 seconds has two uphill tracks that provide a roller-coaster-like experience.

    While the tire slide, which has been successfully tested by almost 10,000 park goers since it opened in February 2018, is impressive, the technology behind it, developed by California startup Ballast is even more so. The specially-created waterproof headsets can be worn in water up to a few meters deep, without harming the delicate Samsung Galaxy S8 mobile devices that run the custom software for the VR experiences. The headsets also charge wirelessly (无线地), allowing park operators to swap out sets throughout the day.

    The biggest challenge the company faced, however, was providing a suitable VR experience for everyone. That's because unlike roller coasters, where the speed is fixed for all riders, water slide speeds vary depending on the weight of the person. To overcome the issue, Ballast fixed  smart sensors (传感器) in important areas along the slide to keep track of the rider's progress at  all times. The information, conveyed through the headset, allows the custom software to adjust his or her location within the virtual world accordingly, making for a smooth, seasickness free ride for all.

    Though Ballast is thrilled at Space Glider's success, the company has bigger ambitions. They want to create an experience where guests will be able to swim underwater surrounded by virtual dolphins, whales, and even sharks, without wearing the heavy headsets!

    One of the best-loved American writers was William Sydney Porter, or O. Henry. From 1893 he lived with his family in a house in Austin, Texas, which is now a museum. Visitors to Austin can see the house. It was saved from destruction (破坏) and turned into a museum in1934. The museum is a good way to learn about the interesting life of the American writer.

    William Porter rented this house in Austin and lived there with his wife Athol and daughter Margaret for about two years. Many objects in the museum belonged to the Porters. Others did not. An important piece in the room is the original photograph over here. It was taken there in the house about 1895. The piano there goes back to the 1860s. His wife took lessons on it when she first moved to Austin.

    Porter did not start his career as a successful writer. He worked at a farm, land office and bank. He also loved words and writing. The museumm has a special proof of Porter's love of language—his dictionary. It is said that he had read every word in that dictionary.

    Later William Porter was forced to leave Austin because he was charged with financial wrongdoing at the bank and lost his job. Because he was afraid of a trail (审判), he left the country secretly. But he returned because his wife was dying. After her death, he faced the trial and became a criminal. He served three and a half years in a prison in Ohio.

    William Porter would keep his time in prison a secret. But there was one good thing about it. It provided him with time to write. By the time he was freed, he had published 14 stories and became well known as O. Henry.

    Porter later moved to New York City and found great success there. He published over 180 stories in the last eight years of his life.