You know that balloons must be kept away from sharp objects. They also needed to be kept away from flames. A fire can weaken the rubber and cause it to break. However, in this experiment you will find out how you can hold a balloon directly in a flame without breaking the balloon.

    Materials needed:

● two round balloons not inflated(充气的)

● several matches

● water

    Inflate one of the balloons and tie it. Place 1/4 cup of water in the other balloon, and then inflate it and tie it. Light a match and hold it under the first balloon. Allow the flame to touch the balloon. What happens? The balloon breaks, perhaps even before the flame touches it. Light another match. Hold it directly under the water in the second balloon. Allow the flame to touch the balloon. What happens to this balloon? It doesn't break.

    Why does the balloon with no water break in the flame? The flame heats the rubber of both balloons. The rubber of the balloon without water becomes so hot that it becomes too weak to resist the pressure of the air inside the balloon. However, when the balloon with water in it is placed in the flame, the water takes in most of the heat from the flame. Then, the rubber of the balloon doesn't become very hot, it doesn't weaken, and the balloon doesn't break.

    Water is a particularly good absorber(吸收者) of heat. It takes a lot of heat to change the temperature of water. On the other hand, when water cools, it gives off a great deal of heat. That's why areas near oceans or other large bodies of water don't get as cold in winter as areas at the same latitude(纬度) further inland.

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    Teens and younger children are reading a lot less for fun, according to a Common Sense Media report published Monday.

    While the decline over the past decade is steep for teen readers, some data in the report shows that reading remains a big part of many children's lives, and indicates how parents might help encourage more reading.

    According to the report's key findings, "the proportion (比例) who say they 'hardly ever' read for fun has gone from 8 percent of 13-year-olds and 9 percent of 17-year-olds in 1984 to 22 percent and 27 percent respectively today."

    The report data shows that pleasure reading levels for younger children, ages2-8, remain largely the same. But the amount of time spent in reading each session has declined, from closer to an hour or more to closer to a half hour per session.

    When it comes to technology and reading, the report does little to counsel(建议)parenst looking for data about the effect of e-readers and tablets on reading. It does point out that many parents still limit electronic reading, mainly due to concerns about increased screen time.

    The most hopeful data shared in the report shows clear evidence of parents serving as examples and important guides for their kids when it comes to reading. Data shows that kids and teens who do read frequently, compared to infrequent readers, have more books in the home, more books purchased for them, parents who read more often, and parents who set aside time for them to read.

    As the end of school approaches, and school vacation reading lists loom(逼近)ahead, parents might take this chance to step in and make their own summer reading list and plan a family trip to the library or bookstore.

    Jack London, one of America's major writers of adventure tales, was born in California in 1876. During his life, London worked at many jobs. His broad life experiences would become the background for his writing.

    London loved to read. As a teenager, he spent many hours educating himself at the Oakland, California, public library. He attended college at the University of California at Berkeley, but he stayed for only six months. He thought Berkeley was “not lively enough” and wanted to do something more exciting.

    London wrote stories about working people and the hard times they had making a living. He knew their problems first hand. He worked as a sailor, farmer, factory employee, railroad worker, and gold prospector, to name just a few of his many jobs.

    London grew up near the waterfront in Oakland. He loved the water. When he was fifteen years old, he bought a small sailboat called a sloop. Later he sailed to Japan on a schooner, which is a much larger sailing boat. Like many people of the time, London caught the Klondike Gold Rush Fever. In 1897, he headed for Alaska. He didn't find gold, but he discovered something even more valuable. He discovered that people enjoyed listening to the stories he made up with his vivid imagination. London entertained the miners with story after story. Later, using his experiences during the Gold Rush, he created many more colorful stories.

    London resolved to live a full, exciting life. He once said, “I would rather be a superb meteor(流星), every atom of me in magnificent glow, than a sleepy and permanent planet.” Each day, he pushed himself. Once London determined that he was going to be a writer, nothing could stop him. His goal was to write at least one thousand words every day. He refused to stop even when he was sick. In eighteen years, the writer published fifty-one books and hundreds of articles. He was the best-selling and highest-paid author of his day. Many people also considered him to be the best writer. White Fang and The Call of the Wild are his most famous stories and are about surviving in the Alaskan wilderness. Readers can enjoy Jack London's energy and his talent for telling wonderful stories each time they open one of his novels.

    Every year, millions of people head to London's Trafalgar Square to see Nelson's Column, and the four lion statues that “guard” it. And last month, during the London Design Festival, a bright red lion sculpture was added to the collection.

    But this was more than just a statue: It had a large open mouth, with an LED screen inside it. At the same time, passersby could type in random words on a screen close to the lion, which were used to produce an AI-created poem. The most interesting part of the poems lies in their randomness, as the words that people choose to enter include many things, such as the time, the weather and their mood. In the daytime, the finished poem appeared on the LED screen, but at night, it was projected (投射) onto the lion's body and the famous Nelson's Column, in a 1ovely light display.

    Es Devlin, the sculpture's creator, was inspired by the history behind the four historic lion statues. Edwin Landseer, the designer of the lions, wanted them to look much more animated, but Queen Victoria refused his plan. This made Devlin wonder, "What if we could give a lion a poetic voice?" According to Devlin, although England has seen many poems about national identity in recent years, these works have been lacking imagination. "I wanted to make a piece that was poetic and collective" he told BBC News.

    After standing for almost 180 years, the purpose of Trafalgar Square has changed over the years. But thanks to the high-tech lion and its poetry, the square is standing the test of time.

    The Bermuda Triangle is an area in the western part of the North Atlantic Ocean, near Florida in the USA, where a number of aircraft and ships are said to have disappeared mysteriously.

    ①The earliest suggestion of unusual disappearances in the Bermuda area appeared in a September 17, 1950 article. Two years later, published "Sea Mystery at Our Back Door", covering the loss of several planes and ships, including the loss of Flight 19. Flight 19 alone would be covered again in the April 1962 issue of American Legion magazine. In it, author Allan W. Eckert wrote that the flight leader had been heard saying, "We are entering white water. Nothing seems right. We don't know where we are." In the February 1964, the article "The Deadly Bermuda Triangle" argued that Flight 19 and other disappearances were just part of strange events in the area.

    ②Triangle writers have used a number of supernatural ideas to explain the events. One explanation refers to leftover technology from the mysterious lost continent of Atlantis. Some of the Triangle writers related the events to UFOs. This idea was used by Steven Spielberg for his science fiction film Close Encounters of the Third Kind, in which the lost Flight 19 aircrews were taken by aliens.

    ③But there are also some explanation relating to nature. For example, laboratory experiments carried out in Australia have proven that bubbles containing natural gas can sink a large ship by decreasing the density(密度) of the water. Because it has been assumed that the eruption of volcanoes(火山)may produce much natural gas, making large areas of bubbles under sea so that water is no longer able to provide enough supporting power for ships. If this were the case, such an area forming around a ship could cause it to sink very rapidly and without any warning.

    ④Violent weather is likely to be another reason. Powerful storms forming in tropical(热带的)waters have caused thousands of deaths and caused billions of dollars in damage. These storms have in the past caused a number of incidents related to the Triangle.

    Have you ever noticed how Americans fill up their entire glass with ice and then pour their beverage (饮品) in, but Europeans take their drinks at room temperature? In the U. S. , we've created fridges that give you cold ice at the press of a button, but in Britain they typically serve their tap water warm.

    This tradition—if that's what you want to call it—dates back to the 19th century. During that time, it was already commonplace for most American homes to have an ice box. Ice would be harvested in northern America or Canada and shipped across the Atlantic and sold at a high price in British department stores. Can you imagine heading to Macy's to treat yourself to a block of ice?

    Putting ice in your drink started to become somewhat of a fashion(时尚)trend for the wealthy in Britain. Some would put a few cubes in their champagne and sip on their chilled drinks at high-class parties. But, like with any fashion trend, it eventually faded, mainly because the ice was just too expensive. And even once ice boxes began appearing in homes in Britain as well, Brits never took a liking to ice in their drinks.

    So, next time you travel overseas, don't feel offended (被冒犯) when your server gives you an eye roll when you ask for ice water.