Five years ago, David Smith wore an expensive suit to work every day. "I was a clothes addict(有瘾的人)," he jokes. "I used to carry a fresh suit to work with me, so I could change if my clothes got wrinkled(有褶皱的)." Today David wears casual clothes (便装) to the office. He hardly ever wears a necktie. "I am working harder than ever." David says, "and I need to feel comfortable."

More and more companies are allowing their office workers to wear casual clothes to work. In the United States, the change from formal to casual office wear has been gradual. In the early 1990s, many companies allowed their employees to wear casual clothes on Friday. This became known as "casual Friday". "What started out as an extra one-day-a-week benefit for employees has really become an everyday thing." said business consultant Maisly Jones.

Why have so many companies started allowing their employees to wear casual clothes? "One reason is that it's easier for a company to attract new employees if it has a casual dress code." "A lot of young people don't want to dress up for work," says Owen Black, the owner of a software company, "so it's hard to hire people if you have a conservative (保守的) dress code." Another reason is that people seem happier and more productive when they are wearing comfortable clothes. In a study conducted by Levi Company, 85 percent of employers said that they believe that casual dress improves employee morale (心境, 士气). Only 4 percent of employers said that casual dress has a negative influence on productivity. Supporters of casual office wear also argue that a casual dress code helps them save money. "Suits are expensive, if you have to wear one every day," one person said. "For the same amount of money, you can buy a lot more casual clothes."

    In the story of “The crow and the Pitcher” from Aesop's Fables, a thirsty crow(乌鸦) drops stones into a narrow jar to raise the low level of water inside so he can take a drink.

    Now scientists have evidence to back up that story. New Caledonian crows actually do understand how to make water displacement work to their advantage, experiments showed. The results suggest that the birds are, at least in some aspects, as smart as first-graders, according to the study.

    Researchers, led by Sarah Jelbert at the university of Auckland in New Zealand, presented six crows with tubes filled with water. Inside the tubes, a worm or piece of meat on a piece of wood was floating, just out of reach of the crow. In front of the tubes, the researchers arranged a bunch of heavy rubber erasers that would sink, and light plastic objects that would float. The crows found out that they could drop the heavy objects into the tubes in order to raise the water level and get their snack.

    However, the birds handled awkwardly in experiments in which they could choose to drop objects in either a wide tube or a narrow tube to get a snack, the researchers said. Dropping objects into narrow tube would lift the water level by a greater amount and put the treat within reach after just two drops. In contrast, it took around seven drops to raise the snack to the same level in the wide tube. The crows obviously didn't realize this, and most of them went for the wide tube first.

    Previous studies showed that chimps and human children can solve similar tasks. In a 2011 study, chimps and kids found out that they could put water into a tube to reach a peanut that was floating in small amount of water at the bottom.

    The world seems gloomy (阴沉的) and gray when you're feeling blue. In fact, being down might even affect how you perceive (感知) the colour blue. A recent study about colour was published in the journal Psychological Science. It shows a direct connection between a person's ability to perceive colour and their emotions.

    Psychologists have long known that emotions can affect the way people perceive things. That's in part because chemicals from your brain might affect how you process what you see. “Color is such an important part of our experience,” says lead author Christopher Thorstenson, a psychologist at the university of Rochester, in New York. There's reason, he says, that sad people commonly describe the world as “colourless” and “gray”, and happy people use words like “bright” and “colorful”.

    In the experiment, the researchers randomly assigned people to one of two groups. People in the sadness group watched a sad scene from The Lion King. Those in the “amusement” group watched a comedy.

    Everyone was then asked to look at red, yellow, green, and blue patches (斑点) that had been changed to a grayish colour. “Some of the patches are pretty difficulty to make out,” Thorstenson admits he says it takes some time to figure out their shade. People were scored on how accurate their colour perception was. Then they completed an emotional evaluation.

    The result? Sad people had a hard time seeing the difference between shades along the blue-yellow colour axis (色轴). But they did not have problems seeing colours in the red-green spectrum (光谱). Thorstenson says this could be the result of an evolutionary need to see red as a response to anger.

    Thorstenson says these results highlight the possible important of dopamine in sight. Dopamine is a chemical that sends signals to the brain. Researchers are hoping to focus more on dopamine in the future. “We know dopamine affects how we see colours, too,” Thorstenson says “How we feel can really influence how we see the world around us” he says.

    When you are travelling, whether on business or for pleasure, you often need to stay in a hotel. The kind of hotel you choose probably is decided above all according to how much money you want to spend. There are small hotels with very few services, where the prices are low, or there are large hotels with all the very latest comforts, where you could spend all the money you have in the bank for one very comfortable night.

    There are several different kinds of people who go to hotels. Some want to live, rather than just stay, in a hotel; the hotels which are designed to meet their needs are called residential hotels. However, most people who stay in hotels are either business people or tourists on holiday.

    In most hotels, there are two kinds of rooms: single rooms, for the use of one person, and double rooms, for the use of two people. In addition, in large hotels, there are also suites(套房), which include two or more rooms connected together—perhaps a bed-room and a living room. They are for people who are very rich or very important.

    Running your small business requires good staff. Once you find them, you don't want to let them go elsewhere.

    During an employee's time with a company, there are a number of forces that influence his or her behavior. I like to refer to them as "push" and "pull". You're either pushing an employee towards the door, or pulling them deeper into your organization.

    Suppose that you've made a good hire and you want to keep the employees, the trick is to recognize individual needs of employees and satisfy those needs, within reason, in order to keep pulling them away from the door. Even if you can't pull them away from the door, at least don't do things to push them out of the door.

    Recognize that some employees will lose interest and need something fresh to keep their interest. If you can't continually provide challenges, opportunities for promotion and other interesting and rewarding opportunities, then you'll have some employees leave through no fault of your own.

    The important thing is to identify your key employees and make certain they are being treated well. Communicate with them on a regular basis to make certain that you understand what makes them behave in a particular way, and be aware of concerns they may have about job satisfaction.

    Sports accounts for a growing amount of income made on the sales of commercial time by television companies. Many television companies have used sports to attract views from particular sections of the general public, and then they have sold audiences to advertisers.

    An attraction of sports programs for the major U.S. media company is that events are often held on Saturday and Sunday afternoons — the slowest time periods of the week for general television viewing. Sport events are the most popular weekend programs, especially among male viewers who may not watch much television at other times during the week. This means the television networks are able to sell advertising time at relatively high prices during what normally would be dead time for programming. Media corporations also use sports to attract commercial sponsors that might take their advertising dollars elsewhere if television stations did not report certain sports. The people in the advertising departments of major corporations realize that sports attract male viewers. They also realize that most business travelers are men and that many men make family decisions on the purchases of computers, cars and life insurance.

    Golf and tennis are special cases for television programming. These sports attract few viewers, and the ratings(收视率) are unusually low. However, the audience for these sports is attractive to certain advertisers. It is made up of people from the highest income groups in the United States, including many lawyers and business managers. This is why television reporting of golf and tennis is sponsored by companies selling high-priced cars, business and personal computers, and holiday trips. This is also why the networks continue to carry these programs regardless of low ratings. Advertisers are willing to pay high fees to reach high-income consumers and those managers who make decisions to buy thousands of "company cars" and computers. With such viewers, these programs don't need high ratings to stay on the air.