Disposing (处理) of waste has been a problem since humans started producing it. As more and more people choose to live close together in cities，the waste disposal problem becomes increasingly difficult.

    During the eighteenth century，it was usual for several neighboring towns to get together to select a faraway spot as a dump site. People would transport household rubbish，rotted wood and old possessions to the site. Regularly some of the trash was burned and the rest was buried. The unpleasant sights and smells caused no problem because nobody lived close by. Factories and some other industrial sites also had waste to be disposed of. Those located on rivers often just poured the unwanted remains into the water. Others built huge burners with chimneys to deal with the problem.

    Several facts make these choices unacceptable to modern society. The first problem is space. Dumps(垃圾场)， are most needed in heavily populated areas. Such areas rarely have empty land suitable. Farm areas are refusing to accept rubbish from elsewhere，cheap land in major city areas to dispose wastes is nonexistent(不存在的). Awareness of pollution dangers has resulted in more strict rules of waste disposal. Pollution of rivers，ground water，land and air is a price people can no longer pay to get rid of waste. The amount of waste，however， continues to grow.

    Recycling efforts have become commonplace，and many towns require their people to take part. Even the most efficient recycling programs，however，can hope to deal with only about 50 percent of a city's reusable waste，so more people should be involved in recycling programs.

    Across Britain, burnt toast will be served to mothers in bed  this morning as older sons and daughters to deliver their supermarket bunches of flowers, But, according to a new study, we should be placing a higher value on motherhood all year.

    Mothers have long known that their home worked was just heavy as paid work. Now, the new study has shown that if they were paid for their parental labors, they would earn as much as￡172,000 a year.

    The study looked at the range of jobs mothers do, as well as the hours they are working, to determine the figure. This would make their yearly income ￡30, 000 more than the Prime Minister earns.

    By analyzing the numbers, it found the average mother works 119 hours a week,40 of which would usually be paid at a standard rate 79 hours as overtime. After questioning 1,000 mothers with children under 18,it found that ,on most days, mums started their routine work at 7am and finished at around 11pm.

    To calculate just how much mothers would earn from that labor, it suggested some of the roles that mums could take on, including housekeeper, part-time lawyer, personal trainer and entertainer. Being a part-time lawyer, at ￡48.98 an hour, would prove to be the most profitable of the “mum jibs”, with psychologist（心理学家）a close second.

    It also asked mothers about the challenges they face, with 80 percent making emotional（情感的）emand as the hardest thing about motherhood.

Over a third of mums felt they needed more training and around half said they missed going out with friends.

    The study shoes mothers matter all year long and not just on, Mother's Day. The emotional, physical and mental energy mothers devote to their children can be never-ending, but children are also sources of great joy and happiness. Investing（投入）in time for parenting and raising relationships is money well spent.

    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 color blue. A recent study about color was published in the journal Psychological Science. It shows a direct connection between a person's ability to perceive color 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 “colorless” 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 color. “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 color 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 color axis(色轴). But they did no have problems seeing colors 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 colors, too,” Thorstenson says “How we feel can really influence how we see the world around us” he says.

    Most nations have at least one type of food that people from other countries think is unusual or unacceptable to eat. In France, people eat horse meat and frog legs. In South Korea and parts of China, restaurants serve dog meat. And in Australia, it's common to cook kangaroo meat on the barbecue and use emu eggs to make pancakes.

    The kangaroo and emu are native to Australia. Both animals are important to the national image of Australia and appear on the Australian coat of arms. They're also central figures in the history of the native Australians. However, they still hunt these animals for their meat, fur and fat.

    Today, Australian people continue to eat these animals. One of the reasons people eat kangaroo meat is that it's high in protein and low in fat, so eating kangaroo is a good option for anyone on a diet. It's also cheaper to eat kangaroo meat than other red meats. Because of this, a lot of university students choose to buy kangaroo meat. BBC News also reported that Australian scientists believe that eating kangaroo meat is good for the environment— kangaroos have different digestive systems than cows and sheep, meaning they produce less methane, the second biggest contributor to global warming.

    While emu meat is high in iron and vitamin C, most people don't think it tastes good. For this reason, they prefer emu eggs. One egg is large enough to make seven omelettes (煎蛋). And while ifs illegal to collect emu eggs from the wild, they can be bought from emu farms. Rather than cracking the beautiful dark shell, it's better to dry it by putting a small hole at each end and blowing. Afterwards, you can even carve a design into the eggshell.

    Most Americans are worried about new technology. They are concerned that machines, including robots, will take over work now done by humans. These findings come from a new report by the Pew Research Center of Washington D. C.

    About 75 percent of Americans questioned by Pew said automation will increase income inequality between the rich and the middle class and poor. And 64 percent of people expect automation to be so common in America that people will face difficulty finding things to do with their lives.

    Some of the concerns about technology come from a distrust about whether machines will always make the right decision. Many Americans believe humans have better judgement in dealing with. complex matters. One example is selecting a person for a job. Three-quarters of Americans said they would not want to apply for a job that uses a computer program to choose the most qualified person.

    “Most Americans want the government to limit automation. For example, 87 percent support a requirement that all driverless vehicles have a human in the driver's seat who can take control when an emergency occurs. And 85 percent want to limit machines to mostly doing jobs that are dangerous or unhealthy for humans. And only 25 percent expect more jobs to come from automation,” Pew said.

    Mark Zuckerberg, the co-founder of Facebook, spoke last May to graduating seniors from Harvard University in Massachusetts. His talk centered on the uncertain future facing young people. “Our generation will have to deal with tens of millions of jobs replaced by automation like self-driving cars and trucks.” Zuckerherg told the graduates.

    Zuckerberg said young people had better launch(发起)projects that will bring both jobs and direct benefits to the people of the world. He said in his speech that 30000 people worked to put a man on the moon, and millions of people built the Hoover Dam as well as other great projects over the last 100 years.

    About three decades ago, China was known as the "Bicycle Kingdom". But later on, bikes were replaced by their fuel-powered competitors.

    But recent months have seen a recovery of the humble bike across China, with an increasing number of people choosing cycling instead of driving to schools, to workplaces or to do sightseeing. The introduction of bike-sharing schemes, pioneered by start-ups like Ofo and Mobike, has brought the trend to a new level.

    People can unlock the shared bikes by simply using their smartphone. The bikes are equipped with GPS and can be left anywhere in public for the next user. They're popular among many Chinese people as they provide an effective solution to the "last mile" problem, which refers to the final leg of a person's journey.

    " In places where the subway doesn't extend, where it's difficult to change from one kind of transport to another, it's so easy to get where you want to go with Mobike," Hu Hong,29,told AFP. She pedals(骑车)to her Shanghai real-estate job.

    However, the schemes have also led to problems such as illegal parking, vandalism(故意毁坏) and theft. Last month, two nurses in Beijing were placed under administrative punishment for five days for putting locks on two shared bikes. And in December, a man who stole a shared bike was sentenced to a 3-month detention(拘留),and fined 1 ,000 yuan by the Shanghai Minhang People's Court.

    " Bike-sharing is a greener method of transportation and provides a user-friendly experience,"said Liu Xiaoming, vice-minister of transport.

    " But it's a combination of online and offline business. Operators are usually strong in online services, but lack offline business experience, which causes problems."

    Now, Chinese service operators are trying to solve the problems. For example, a bike- sharing company called Mobike sets a 100-point credit score for each user, with points taken in the case of bad behavior. Once a score drops below 80, bike rental is increased to 100 yuan per 30 minutes, up from 0.5 - 1 yuan.