We often find that weekends and holidays feel so short while classes and work feel so long. Actually, though, we know that this is not true. But we still wonder where that strange feeling comes from.

    In fact, this is one of the ways that we're tricked by time, according to the website. All that S interesting. The website lists several wrong impressions (印象) we often have about time. Let's have a look.

    First of all, emotions affect (影响) our time-keeping abilities. Negative emotions (消极情绪). especially anxiety and boredom, make time seem longer because they make us concentrate (集中) more on the passage of time. However, when we are enjoying ourselves, we pay more attention to what we are doing and are likely to lose track of (失去对……的意识) time.

    Here is another example. In 2007, a group of scientists carried out a test. In the test, people fell 50 meters into a safety net and were then asked about their experience. Although the experience took shorter than 3 seconds, the people thought it was much longer than it actually was.

    This is because of the way our bodies reply to danger, according to the scientists. Our bodies produce a chemical called adrenaline (肾上腺素) when we are faced with danger. It allows us to concentrate better so that we can stay alive. As a result, we are able to remember far more details (细节) over a short period of time, which makes it seem like time is going more slowly.

    Another situation when we make mistakes about time is when we take afternoon naps (午觉). Have you ever had trouble telling what time it is after a long nap? That's because the best amount of time for a nap is 20 minutes. After 20 minutes, you enter a new stage of sleep called slow-wave sleep. If you wake up mid-way in this stage, it will take a while before you can correctly perceive (感知) time again.

    Yes, time can be mysterious (神秘的) and there is no way to control it. So, perhaps the best thing to do is to make good use of every minute.

    Vienna is a beautiful old city on the River Danube in the center of Europe. It's the capital city of Austria and the center of European classical music. In the 18th century a lot of musicians came to study and work in Vienna.

    In the Strauss family, there were two composers called Johann Strauss: the father and the son. The father, Johann Strauss the elder, wrote and played music for traditional dances, called the waltz. His dance music made him famous all over Europe. The son, Johann Strauss the younger, was also very successful and popular. He wrote over 150 waltzes. In 1867 he wrote The Blue Danube waltz.

    Mozart was another very important composer. He was born in Austria in 1756. Before he was six, he played not only the piano but also the violin. His family took him around Europe and he gave concerts in many cities. He wrote hundreds of wonderful pieces of music. But he became very poor and died in 1791 when he was only 35. Like Johann Strauss, father and son, he was a great European musician, and many people still think his music is perfect.

    Horses are beautiful animals. They can be in different colors, and can run quickly. People like to watch horses because they are strong and beautiful.

    Horses are mammals (哺乳动物). The mother horse usually has one baby in spring, and feeds the baby milk. Horses have long legs and big eyes, so they can see almost all the way around them. They can walk and jump.

    Horses can live up to 20 or 25 years. Sometimes people can tell how old a horse is by looking at its teeth! They usually sleep by standing up. Horses only need about three hours of sleep per day!

    People need to take care of the horses"hooves". If a horse is doing a lot of walking on hard ground, people put horseshoes on them. When the hooves need trimming (修剪), people take off the horseshoes, and then give them new ones.

    For food, horses eat food such as grass, corn, apples and carrots. They don't eat other animals. Their stomachs are small, so they eat a little at one time, but they eat many times.

    Some horses are very famous. For example, Bucephalus, the famous horse of Alexander the Great. When Alexander was a boy, he got a horse. Nobody else could ride on it. Alexander named the horse Bucephalus and the horse carried him in many battles (战役). Here is another example. Napoleon had many horses, and Marengo became famous after Battle of Waterloo.

Scientists say they recently invented the world's tiniest remote—controlled robots. The robots are small enough to sit on the side of a coin. They don't have any power of their own，and they can be controlled from a distance by using lasers（激光器）. The scientists say one day robots like these may be able to work in areas too small for tools. The robots don't move very quickly. But because of their tiny size，they're also not too slow. It takes the robots about 20 seconds to cover 1 centimeter. 

Right now the robots aren't all that useful. All they can do is to move，and they need to be in a place where lasers can shine on them to do that. But the scientists say these robots are an important step toward inventing more helpful tiny robots. 

The researchers say that one day tiny robots like these might be able to work in very small spaces. It's possible that they could build very tiny machines，or perhaps even travel inside the human body to help do with medical problems. 

Using similar building methods，the scientists made a number of different robots，including ones that looked like small insects. John Rodgers，says that their methods allow them to "build walking robots with almost any sizes or 3 D shapes. "

Do you think English is difficult? If so, you are not the only one. Many students feel it difficult to remember new words when they begin to study English. Now Ms. Manson, an English teacher, will give you some advice.

⑴Do not waste time in learning a list of English words. It is the hardest way to remember English words. How do you learn to speak Chinese? You did it by listening carefully to the people talking to each other. You can find radio programs, TV programs and records, and listen to them carefully. The best way to learn all new words is through ears. As you listen to more and more dialogues, you will learn how English is pronounced in phrases and sentences. Of course, it is not enough to learn new words. You must learn how words are put together, and why some words in English are emphasized(重读).

⑵Some people have found that they can learn the names of everyday objects such as boxes, bottles, cups and desks in the following way. They write the names of objects on paper and put the paper on them, then say the words. Try this and see if this way works for you. If it does not, then go on to practice your dialogues.

Do you like travelling？Travelling is one of the most popular activities during holidays. Modern traffic develops fast，so travelling to different places gets much easier than before. 

Travelling can keep you healthy，and can make your trip happier. But do you know how to keep healthy during a trip？The following information may be useful to you. 

Before leaving

★Wear comfortable shoes，a hat and sunglasses. 

★Take some necessary （必需的） medicines with you. You will need them when you get sick or have other problems. 

★If you do lots of sports like walking or climbing during your trip，you should do some exercise for weeks or months before you leave. While travelling

★Be sure not to eat dirty food or bad fruit. 

★Have enough time to take a rest during your trip. 

★Tap （水龙头） water is not safe，so drink bottled water. When you drink it，remember to clean the cover of the bottle. There may be something dirty on it，such as dust （灰尘）.