EUROPE is home to a variety of cultural treasures. Lonely Planet, the world's largest travel guide publisher, has offered pairs of cities for culture-hungry but time poor travelers.

    London and Paris

    It takes you about two hours to travel from London to Paris by Eurostar, a high-speed railway service. The two capital cities have been competing in fashion, art and nightlife for decades — but each secretly looks up to the other.

    No one can doubt the grand and impressive beauty of Paris' Louvre Museum, but if you want to save money, you cannot skip the British Museum free to visit. Compared with London, Paris has more outdoor attractions, such as the beautiful green walkway La Promenade Plantee.

    In Paris, you'll see diners linger(逗留) over red wine. While in London, you can try some afternoon tea, eat fish and chips or salted cake.

    Vienna and Bratislava

    Austrian capital Vienna and Slovakia city Bratislava are an hour apart by train. But since they are linked by the Danube River, the best way to travel is by ship. A tour of the two cities is the perfect way to experience everything from 17^th century's Habsburg dynast splendor to sci-fi restaurants.

    Vienna is famous for Mozart and imperial palaces. You can appreciate the perfect blending(融合) of architecture and nature in the grand Scholoss Schonbrunn Palace, and reward yourself with a cup of Vienna coffee, which has made its way to the world's cultural heritage.

    Bratislava is best known for its fine dining—the remarkable UFO restaurant. You can enjoy a meat-filled dinner here in an amazing setting.

    A warm drink of milk before bed has long been the best choice for those wanting a good night's sleep. But now a study has found it really does help people nod off（打瞌睡）—if it is milked from a cow at night.

    Researchers have discovered that “night milk” contains more melatonin(褪黑激素), which has been proven to help people feel sleepy and reduce anxiety（焦虑）.The study, by researchers from Seoul, South Korea, involved mice being fed with dried milk powder（奶粉） made from cows milked both during the day and at night. Those given night milk, which contained 10 times the amount of melatonin, were less active and less anxious than those fed with the milk collected during daytime, according to the study published in The Journal of Medicinal Food.

    Night milk quickened the start of sleep and caused the mice to sleep longer.

    While the effect of cow milk harvested at different time has not been tested on humans up to now, taking melatonin drugs has been suggested to those who have trouble falling asleep at night.

    Previous （以前的）studies have also showed that milk can be excellent for helping sleep because of the calcium content, which helps people to relax.

    Unlike most other holidays, the history of April Fools' Day, sometimes called All Fools' Day, is not totally clear. The only point in time that can be agreed on as the beginning of this tradition was 1582, in France. Before that year, the New Year was celebrated for eight days, beginning on March 25th. The celebration reached the highest point on April 1st. With the reform of the calendar under Charles IX，the Gregorian calendar(公历，阳历) was introduced, and New Year's Day was moved to January 1st.

    However, because in those days communications were not as developed as they are today, many people did not receive the news for several years. Some people refused to accept the new calendar and continued to celebrate the New Year on April 1st. These backward people were considered "fools" by other people. They  were often sent on "fools" errands(徒劳无益的工作)  or were made the targets of jokes.

    This developed, over time, into a tradition of playing a trick on someone on the first day of April. The tradition eventually spread to England and Scotland in the eighteenth century. It was later introduced to the American colonies of both the Britain and France. April Fools' Day thus developed into an international fun feast, so to speak, with different nationalities specializing in their own kind of humor at the expense of their friends and families.

    Ride-hailing apps and robot cars promise to change how we get around and the effects are already being felt. Traffic in New York is slowing down. Jams are common in Manhattan, especially in its business districts. Daytime traffic in the busiest areas now moves almost 20% more slowly than it did five years ago.

    It seems a place ripe for wide use of ride-hailing apps that, you might think, would reduce some of the jams. However, those apps appear to be making things worse as traffic has slowed in line with the growing popularity of apps such as Uber and Lyft, a study by transport expert Bruce Schaller suggests.

    Over the four years of the study, the number of cars in Manhattan seeking ride-hailing fares increased by 81%. There are now about 68, 000 ride-sharing drivers across New York. That's about five times the number of the yellow cabs licensed to operate there, he found. There are so many drivers, his work suggests, who spend about 45% of their spare time just touring for fares. That is a lot of unused cars blocking a lot of busy streets.

    Simple physics explains why ride-sharing vehicles are causing, not curing jams, said Jarrett Walker, a public transport policy expert who has advised hundreds of cities about moving people.

    "Lots of people are deciding that, 'Oh, public transport is just too much trouble this morning,' or whenever, which causes a shift from it," he told the BBC. "That means moving people from larger vehicles into smaller ones, which means more vehicles to move the same people. Therefore, more traffic."

    Data gathered about ride-sharing drivers illustrates how they contribute to congestion (塞车), said Prof. Christo Wilson, a computer scientist at Northeastern University who has studied the services. "You can look at the traffic pattern for the Uber vehicles and it perfectly matches the peaks for the rush hour and the peak time of a day," he said. They are out there in force at the worst possible times.

    This year marks the 170th anniversary of Paul Gauguin's birth. He lived for just 54 years but he packed his brief life with activity.

    The French painter spent his early childhood in Peru before returning to France. As an adult, he continued to travel a lot. Most famously, he spent much of the last decade of his life in Tahiti, an island in southern Pacific Ocean. Indeed, Gauguin is best known for his colorful paintings of Tahitians and their culture.

    The restlessness of this great painter has been normal among modern artists since the middle of the 19th century. They're never satisfied for long with a certain style or way of life. Once something becomes conventional, it's turned down.

    The artistic culture that Gauguin developed from was that of Impressionism (印象派). Painters like Claude Monet had wanted to paint how they saw the world, not how their teachers taught them it should be seen. Gauguin, and similar artists like his friend Vincent van Gogh, moved even further away from "respectable" art than the Impressionists. For them, it was not simply a matter of seeing the world differently, but feeling and thinking about it differently, too.

    Gauguin saw, felt and thought differently from most members of European society. He thought that European culture was too fancy and not spontaneous. This is why he turned to the traditions of other parts of the world, like Africa, and, eventually, Tahiti. Artists like Gauguin used the word "primitive" for these cultures, but not as a negative term. For him, Europe, in becoming modem, industrial and scientific, seemed less natural than other parts of the world.

    In truth, Gauguin's paintings may be unconventional but they are certainly not "primitive". They are the work of a painter with great awareness of what he was doing. It was this awareness that made him such an important painter for those that came after, in the 20th century. When we look closely at the works of Gauguin we begin to understand Pablo Picasso, and especially Henri Matisse, a little better.

    Travelling can be a fun way to gain life experiences, especially during a week-long school vacation. But what if you're a student and don't have enough money for a trip? Don't worry.

Here are some useful tips.

    Save: This probably is the most important preparation for travelling. Cut expenses to fatten your wallet so you'll have more choices about where to go and how to get there.

    Plan ahead: Don't wait until the last minute to plan your trip. Tickets may cost more when bought on short notice. Giving yourself several months to get ready can mean security(安全)and savings.

    Do your homework: No matter where you go, research the places you will visit. Decide what to see. Travel books will provide information on the cheapest hotels and restaurants.

    Plan sensibly(明智地): Write down how much you expect to spend for food and hotels. Stick to your plan or you may not have enough money to cover everything.

    Travel in groups: Find someone who is interested in visiting the same places. By travelling with others you can share costs and experiences.

    Work as you go: Need more money to support your trip? Look for work in the places you visit.

    Go off the beaten path: Tourist cities may be expensive. You may want to rethink your trip and go to a lesser-known area. Smaller towns can have many interesting activities and sights.

    Pack necessary things: The most important things to take are not always clothes. Remember medicine in case you get sick and snacks in case you can't find a cheap restaurant.

    Use the Internet: The Net can help to save money. Some useful websites include www. Iravelocity.com, www.bargains-lowest fare.com and www.Economy travel.com.

    By planning sensibly, even students can enjoy the travel. Your travel experiences will be remembered for a lifetime.