Elephants on the coast of Thailand are acting strange.They stamp their feet and motion toward the hills.The sea draws back from the beaches.Fish fall heavily in the mud.Suddenly,a huge wave appears.This is no ordinary wave.It is tsunami!

    Tsunami waves are larger and faster than normal surface waves.A tsunami wave can travel as fast as a jet plane and can be as tall as a ten-story building.Imagine dropping a stone into a pond.The water on the surface ripples（起涟漪）.A tsunami is like a very powerful ripple.Tsunamis begin when the ocean rises or falls very suddenly.Large amounts of seawater are displaced.This movement caused huge waves.

    For a tsunami to occur,there must be some kind of force that causes the ocean water to become displaced.Most tsunamis are caused by underwater earthquakes.However,volcanoes ,landslides（塌方）,large icebergs,and even meteorites（陨石）are capable of causing one of these mighty waves.

    Tsunamis are extremely powerful.Ordinary waves lose power when they break.Tsunami waves can remain powerful for several days.Because tsunami waves are so strong,they can kill people,damage property,and completely ruin an ecosystem in just one hour.

    Scientists have no way of predicting when a tsunami will hit.However,if a powerful enough earthquake occurs, scientists can send out a warning or a watch.A warning means that a tsunami will very likely hit soon.A watch means that conditions are favorable for a tsunami.When people are informed of a watch or a warning,they have more time to prepare.It is best not to get caught unaware when a tsunami is on the way.

    Singapore's public transport system is one of the best in the world, so you should have no problem finding your way around like a local. There are three main forms of public transport that you would find in any other major city－trains, buses and taxis.

TRAINS

    Trains run from 6:00 am to midnight. Single trip tickets start at 80 cents. If you buy an EZ-Link card for $15, you can ride the trains and buses as you like.

If you need more information, just call Transit Link on 1800 767 4333.

BUSES

    There are several bus services in Singapore and fares start at 80 cents. Be sure always ask the driver the cost of your ticket as he cannot give change.

If you need help, just call Transit Link on 1800 767 4333.

TAXIS

    There are three main taxi companies－City Cab (6552 2222), Comfort (6552 1111) and Tibs (6552 8888). Booking can also be easy by calling the numbers listed above.

RENTAL CARS

    Driving in Singapore is a pleasure and if you like to travel at your own pace, renting a car is a good choice. Renting takes away the hassle of getting to places around Singapore. Just sit back and enjoy the city. It also means you'll get to see a lot more that a trains or a bus won't let you see.

    For car rental, call Avis on +65 6737 1668.

    US people are overweight, eat lots of fast food and fill their homes with pets. At least that's what 21 European teenagers think.

    The students, 18 from Germany and 3 from France, are exchange students. They are studying in the US for a year. After a few days in the US, they said what they thought about the country.

    Most talked about the amount of fast food US people eat. It's not that the students don't eat fast food. They just don't eat as much.

    Laetitia Villeneuve from France said she eats fast food, usually McDonald's, only once or twice a year.

    "I like it," said Nora Koeberle from Germany. "But I couldn't eat it every day. I'd get fat. "

    Students are surprised at how big US people seem.

    "There are fat people in Germany," said Antonia Greimel from Germany. "But not as many as there are here."

    They also spoke about the animals. Silvana Wolfram from Germany said she had heard about how people had lots of pets in the US.

    Other ways of US high schools interested the students.

    For example, Koeberle said she wouldn't be able to play an instrument or sports as part of her classes in Germany. She can in the US.

    But the best thing about US high schools is something the European kids can't get back home. "I do wish we had parties," Koeberle said.

    Eudaimonia is an Ancient Greek word, particularly stressed by the philosophers Plato and Aristotle, which deserves far more attention than it has because it corrects the shortfalls (缺失)in one of the most central, but troubling words in our modem language: happiness.

    When we nowadays try to clearly express the purpose of our lives，it is the word "happiness" that we commonly turn to. We tell ourselves and others that the most important principle for our jobs, our relationships and the conduct of our day-to-day lives is the pursuit of happiness. It sounds like an innocent enough idea, but too much reliance on the term means that we frequently unfairly tend to quit or, at least, heavily question a great many challenging but worthwhile situations. The Ancient Greeks did not believe that the purpose of life was to be happy; they proposed that it was to achieve Eudaimonia, a word which has been best translated as "fulfilment".

    What distinguishes happiness from fulfilment is pain. It is very possible to be fulfilled and—at the same time—under pressure, suffering physically or mentally, overburdened and, quite frequently, in an irritable (易怒的)mood. This is a slight psychological difference that is hard for the word "happiness" to capture, for it's tricky to speak of being happy yet unhappy, or happy yet suffering. However, such a combination is readily accommodated within the respected and noble-sounding idea of Eudaimonia.

    The word encourages us to trust that many of life's most worthwhile projects will sometimes be in conflict with contentment, and yet will be worth pursuing. Properly exploring our professional talents, managing a household, keeping a relationship going, creating a new business venture or engaging in politics... none of these goals are likely to leave us cheerful and grinning on a daily basis. They will, in fact, involve us in all manner of challenges that will deeply exhaust and weaken us, provoke (激怒)and wound us. And yet we will perhaps, at the end of our lives, still feel that the tasks were worth undertaking. Through them, we'll have achieved something deeper and more interesting than happiness.

    With the word Eudaimonia in mind, we can stop imagining that we are aiming for a pain-free existence—and then blaming ourselves unfairly for being in a bad mood. We'll know that we are trying to do something far more important than smile all the time: we're striving to do justice to our full human potential.

    Over the past 10 years, developments in technology have moved the dream of personal fling vehicles closer to reality. The British company Malloy Aeronautics has developed a model of its flying bicycle. The company says its Hoverbike will be a truly personal flying vehicle.

    The company's marketing sales director Grant Stapleton says the Hoverbike is able to get in and out of small spaces very quickly and can be moved across continents very quickly because it can be folded and packed.

    Safety was the company's main concern when developing the Hoverbike. The designers solved this problem by using overlapping rotors(重叠旋翼) to power the vehicle. With adducted rotors(内转旋翼) the rider immediately not only protects people and belongings if he were to hit them, but if the rider ever were to crash into somebody or something, it's going to bring the flying vehicle out of the air. The company is testing two models of the Hoverbike.

    In New Zealand, the Martin Aircraft Company is also testing a full-size model of its personal flying device, called Jetpack. It can fly for more than 30 minutes, up to 1,000 meters high and reach a speed of 74 kilometers per hour.

    Peter Coker, one officer from the company said Jetpack “is built around safety from the start.” In his words, “Reliability(可靠性) is the most important part of it. We have safety built into the actual structure itself, very similar to a Formula One racing car.”

    Jetpack uses a petrol-powered engine. It also has a parachute(降落伞) that can be used if there should be an emergency(突发事件). It opens at very low altitude(纬度) and actually saves both the flying vehicle and the pilot in an emergency.

    Mr. Coker says Jetpack will be ready for sale to the public by the end of 2019. He adds it'll have a price of about $200,000.

    As Internet users become more dependent on the Internet to store information, are people remember less？If you know your computer will save information, why store it in your own personal memory, your brain？Experts are wondering if the Internet is changing what we remember and how.

    In a recent study, Professor Betsy Sparrow conducted some experiments. She and her research team wanted to know the Internet is changing memory. In the first experiment, they gave people 40 unimportant facts to type into a computer. The first group of people understood that the computer would save the information. The second group understood that the computer would not save it. Later, the second group remembered the information better. People in the first group knew they could find the information again, so they did not try to remember it.

    In another experiment, the researchers gave people facts to remember, and told them where to find the information on the Internet. The information was in a specific computer folder(文件夹). Surprisingly, people later remember the folder location better than the facts. When people use the Internet, they do not remember the information. Rather, they remember how to find it. This is called "transactive memory (交互记忆)".

    According to Sparrow, we are not becoming people with poor memories as a result of the Internet. Instead, computer users are developing stronger transactive memories; that is, people are learning how to organize huge quantities of information so that they are able to access it at a later date. This doesn't mean we are becoming either more or less intelligent, but there is no doubt that the way we use memory is changing.