Probably no other musical instrument is as popular as the guitar around the world. Musicians use the guitar for almost all kinds of music. Country and western music would not be the same without a guitar. The traditional Spanish folk music called Flamenco could not exist without a guitar. The sound of American blues music would not be the same without the sad cry of the guitar. And rock and roll music would almost be impossible without this instrument.

    Music experts do not agree about where the guitar was first played. Most agree it is ancient. Some experts say an instrument very much like a guitar was played in Egypt more than 1,000 years ago. Most experts say that the ancestor of the modern guitar was brought to Spain from Persia sometime in the 12^th century. The guitar continued to develop in Spain. In the 1700s it became similar to the instrument we know today.

    Many famous musicians played the instrument. The famous Italian violins Niccole Paganism played and wrote music for the guitar in the early 1800s. Franz Schubert used the guitar to write some of his famous works. In modern times Spanish guitarist Andres Segovia helped make the instrument extremely popular.

    In the 1930s, Les Paul began experimenting to make an electric guitar. He invented the solid-bodied electric guitar in 1946. The Gibson Guitar Company began producing its famous Les Paul Guitar in 1952. It became a powerful influence on popular music. The instrument has the same shape and the same six strings (弦) as the traditional guitar, but it sounds very different. Les Paul produced a series of extremely popular recordings that introduced the public to this music. Listen to this Les Paul recording. It was the fifth most popular song in the United States in 1952. It is called “Meet Mister Callaghan.”

The baby monkey is much more developed at birth than the human baby. Almost from the moment it is born, the baby monkey can move around and hold tightly to its mother. During the first few days of its life the baby will approach and hold onto almost any large, warm, and soft object in its environment, particularly if that object also gives it milk. After a week or so, however, the baby monkey begins to avoid newcomers and focuses its attentions on “mother” — the real mother or the mother-substitute(母亲替代物）.

During the first two weeks of its warmth is perhaps the most important psychological（心理的） thing that a monkey mother has to give to its baby. The Harlows, a couple who are both psychologists, discovered this fact by offering baby monkeys a choice of two types of mother-substitutes — one covered with cloth and one made of bare wire. If the two artificial mothers were both the same temperature, the little monkeys always preferred the cloth mother. However, if the wire model was heated, while the cloth model was cool, for the first two weeks after birth the baby monkeys picked the warm wire mother-substitutes as their favorites. Thereafter they switched and spent most of their time on the more comfortable cloth mother

    Why is cloth preferable to bare wire? Something that the Harlows called contact（接触的） comfort seems to be the answer, and a most powerful influence it is. Baby monkeys spend much of their time rubbing against their mothers' skins, putting themselves in as close contact with the parent as they can. Whenever the young animal is frightened, disturbed, or annoyed, it typically rushes to its mother and rubs itself against her body. Wire doesn't“rub”as well as does soft wire cloth. Prolonged（长时间的）“contact comfort” with a cloth mother appears to give the babies confidence and is much more rewarding to them than is either warmth or milk.

    According to the Harlows, the basic quality of a baby's love for its mother is trust. If the baby is put into an unfamiliar playroom without its mother, the baby ignores the toys no matter how interesting they might be. It screams in terror and curls up into a fury little ball. If its cloth mother is now introduced into the playroom, the bay rushes to it and holds onto it for dear life. After a few minutes of contact comfort, it obviously begins to feel more secure. It then climbs down from the mother-substitute and begins to explore the toys, but often rushes back for a deep embrace（拥抱）as if to make sure that its mother is still there and that all is well. Bit by bit its fears of the new environment are gone and it spends more and more time playing with the toys and less and less time holding on to its “mother.”

    Taking a shower is relaxing. You can hum a song, daydream or think about nothing, leaving the real world behind you. But did you know that showering can also benefit your mind?

    A research by Scott Barry Kaufman, a psychologist from Yale University in the US interviewed over 3,000 people around the world. It turned out that nearly two-thirds of the interviewees said they had experienced new ideas in the shower and were more likely to have them in the shower than at work.

    So why does a simple shower have such magic power? Science can explain it.

    Showering can help to raise our level of dopamine, a hormone (荷尔蒙) closely related to our creativity. “People vary in terms of their level of creativity according to the activity of dopamine”, explained Alice Flaherty, a famous American neuroscientist. “Taking a warm shower can make us feel relaxed and therefore make the dopamine level rise and bring ‘Aha!' moment to us.”

    Besides the chemical changes, showering may give you a break from what you feel you have been stuck with. Especially when you have thought hard all day about a problem, jumping into the shower can keep you from the outside world so that you can focus on your inner feelings and memories. In this way, according to American psychologist Shelley H. Carson, author ofYour Creative Brain, “a showering hour may turn into an ‘incubation (孵化) period' for your ideas.”

    Compared with sitting in front of a computer, taking a shower is something we do less frequently in our daily life. When showering, we get a fresh experience with the change of location, temperature and humidity. “New and unexpected experiences can lead to positive changes in thinking,” explained Kaufman. “Getting off the couch and jumping in the shower may create a distance and force you to think from a new point of view.”

    Showering allows us to enjoy the creative juices of our minds, but it needn't just be the bathroom where you get your inspiration. For instance, Gertrude Stein, a female American writer and poet, got new ideas by driving around a farm and stopping at different cows until she found the one that most inspired her. So try to create your own way to free your mind, whether it's a walk near the ocean, a country drive or reading a book at home.

    Do you want to go abroad to make money? If you've decided to invest（投资）overseas, you may be wondering which countries are the best, and which countries will give you the biggest returns. In some locations, investment is easier than others. Here are the top 4 best countries to invest in housing:

    Italy

    A charming hillside area, Abruzzo makes for a great investment. This beautiful place has lots of local housing resources, and you can buy a home that needs just $45,000. With proper repair, selling for at least four times that much, you can easily make money.

    Argentina

    Central America's Argentina's tourism is popular, so it has a lot to offer locals and tourists alike. This coastal country is affordable, too, especially in the busy city of Buenos Aires. As the city is rapidly expanding, now it's time to get this hot investing opportunity.

    Mexico

    In the south of the border, you can find unbelievable investment. Playa del Carmen will give you the most for your money. Plus its tourism is popular and it's a nice place to visit and easily accessible from the United States.

    Panama

    Historic and lively, Panama is a safe place for shopping. You'll enjoy great tax（税金）benefits in Panama. Panama does not charge income tax for the first 10 years of your investment.

        No matter where you choose to buy, these four countries will provide you with a great location and return on investment.

    Jealousy is such a powerful emotion that at least one study has characterized it as the third leading cause of non-accidental homicide(杀人) in all cultures. In a recently published study, researchers experimented with dogs to see whether they, like humans, have the nature of jealousy.

In an experiment, the authors took 36 dogs—along with their owners—and observed the dogs' behavior as their masters interacted with three non-living objects. One object was a children's book, which they read aloud; another object was a plastic pumpkin lantern; and the third was a mechanical stuffed dog that gave out a bark when the owner pressed a button.

    Former studies concluded that babies were probably capable of jealousy. In the experiment, their mothers showed attention to a life-like doll instead of their child, and other objects. The babies were reportedly more likely to respond with “negative” behavior if their mother turned to pay her attention to the doll.

    In the dog experiment, authors instructed the dog owners to push the bark button on the stuffed dog's head, and then speak to it sweetly, while ignoring their own dog. After that, they showed attention to the pumpkin lantern, and read the children's book, while also ignoring their dog.

    It is interesting to see the dogs were far more likely to act aggressively when their owners spoke to the stuffed dog than when they paid attention to the other objects. One-fourth of the dogs snapped at the stuffed dog, while only one dog snapped at the lantern or the book. The dogs were also more likely to push or touch their owners as they interacted with the mechanical dogs, and tried to get in between the owner and the stuffed dog more frequently than the other objects.

    “One possibility is that jealousy developed in species of many young relying on the parents, the young compete for parental resources such as food, attention, care, and affection,” the authors wrote.

    Mr. Lee was in bed and was trying to go to sleep when he heard the bell ring. He turned on the light and looked at his clock. It was twelve o'clock. "Who can it be at this time of night?" He thought. He decided to go and find out. So he got of bed, put on his dressing gown (浴袍) and went to the door. When he opened the door, there was nobody there. "That is very strange." Then he went back to his bedroom, took off his dressing gown, got back into bed ,turned off the light and tried to go to sleep.

    A few minutes later he heard the bell again. Mr. Lee jumped out of bed very quickly and rushed to the door. He opened it, but again he found no one there. He closed the door and tried not to feel angry. Then he saw a piece of paper on the floor. He picked it up. There were some words on it : "It is now after midnight(午夜), so it is April Fool's Day (愚人节). April fool to you!"

    "Oh, it was the English boy next door!" Mr. Lee exclaimed (惊叫) and almost smiled. He went back to bed and feel asleep at once. The bell did not ring again.