{#blank#}1{#/blank#}

    Sleep, as we know, is important to us because it helps restore tired organs and tissues in our body. But how much sleep do we actually need?

{#blank#}2{#/blank#}

    For most of us, eight hours seems to be about the right amount. Yet we know that there are a great many people who get along perfectly with less sleep and some who may even need more. A great deal depends on the way we live. But a good general rule to follow is to sleep as long as we have to in order to feel happy and be able to work at our best when we are awake.

{#blank#}3{#/blank#}

    There are actually different levels of sleep. There is a deep sleep and a shallow sleep. In a shallow sleep our body does not get the same kind of rest as it gets in a deep sleep, so that after eight hours of a shallow sleep we may still feel tired. But a short deep sleep can be very restful.

{#blank#}4{#/blank#}

    Alexander the Great was able to get a deep sleep whenever he needed it. Once, during the night before an important battle, he remained awake longer than anyone else. Then he wrapped himself in a cloak and lay down on the earth. He slept so deeply that his generals had to wake him three times to give command to attack!

{#blank#}5{#/blank#}

    Normally when we go to sleep, our “ sleep center” blocks off nerves so that both our brain and our body go to sleep. One prevents us form wanting to do anything and the other makes our internal organs and limbs go to sleep. But someone will fall asleep (brain sleep) and keep on marching, because his body is not asleep!

    Well, parents, surprise! Lots of us are using Twitter and Facebook to thumb rides, and not just to school. It's awkward to be refused when you call a friend and ask for a ride. But with Twitter, you just look for other people heading the same way.

    It may sound risky, so many teens stay within their own social circles to find rides, and don't branch out beyond friends when asking on Twitter just like me, but to some young people, especially those taking longer trips, stranger danger is less of a concern.

    “I think the digital connection of young people is really important, because younger generations grew up sharing things on line, sharing files, photos, music, etc, so they've been very used to sharing,” said Juliet Schor, a sociology professor at Boston College.

    The sharing economy got big during the recession (经济衰退), allowing people to access more goods, services using technology and even to share costs. And that technology, for me, is what the car was for my mom, a gateway to more freedom, like what my friend Earl says, “The symbol of freedom isn't the car any more because there's technology out there connecting you to a car.”

    According to the researchers at the University of Michigan, 30 years ago, eight in ten American 18-year-olds had a driver's license compared to six in ten today. So it's not that surprising that on my 16th birthday I wasn't rushing to get a license but an iPhone.

“Driving, for young people, does mean they have to disconnect from their technology, and that's a negative. So if they could sit in the passage side and still be connected, that's going to be a plus.” Schor continued.

    To me, another plus is that ridesharing represents something, something much bigger than trying to save money. I see it as evidence that people still depend on each other. My generation shares their cars and apartments the way neighbors used to share cups of sugar. For the system to work, some of us still need our own cars. But until I get my own version of the silver Super Beetle, you can find me on Twitter.

    A machine that takes sweat-laden (浸满汗水的) clothes and turns the sweat into drinking water is in use in Sweden. The machine makes the clothes turn round quickly, heats them to remove the sweat, and then passes the steam through a kind of special material to make purified water.

    Since it has been brought into use, its creators say more than 1000 people have drunk others' “sweat” in Gothenburg. They add the liquid is cleaner than local tap water.

    The device was built for the United Nations' child-focused charity UNICEF to promote a campaign highlighting the fact that 780 million people in the world lack access to clean water.

    The machine was designed and built by the engineer Andreas Hammar, known locally for his appearances on TV tech show “Mekatronik”. He said the key part of the sweat machine was a new water purification part developed by a company named HVR.

    “It uses a technique called membrane distillation (膜蒸馏),” he told the BBC. “We use a special kind of material that only lets steam through but keeps bacteria, salts, clothing fibers and other things out. They have something similar to the International Space Station, but our machine is cheaper to build. The amount of water it produces depends on how sweaty the person is, but one person's T-shirt typically produces 10ml, about a mouthful.”

    The device has been put on show at the Gothia Cup-the world's largest international youth football tournament. Mattias Ronge, chief executive of Stockholm-based advertising agency Deportivo, said the machine had helped raise awareness for UNICEF, but in reality had its limitations.

    “People haven't produced as much sweat as we hoped – right now the weather in Gothenburg is lousy,” Mattias Ronge said. “So we've equipped the machine with exercise bikes and volunteers are cycling like crazy. Even so, the demand for sweat is greater than the supply. And the machine will never be produced in large numbers, since there are better solutions out there such as water purifying pills.”

    Life is kind of like a party. You invite a lot of people, some leave early, some stay all night, some laugh with you, some laugh at you, and some show up really late. But in the end, after the fun, there are a few who stay to help you clean up the mess. And most of the time, they aren't even the ones who made the mess{#blank#}1{#/blank#} They are the ones who matter most. Here are four things real friends do differently:

    They face problems together. A real friend is someone who sees the pain in your eyes while everyone else still believes the smile on your face.{#blank#}2{#/blank#}Just look for someone who will face them with you.

    {#blank#}3{#/blank#}Your word means everything. If you say you're going to do something, DO IT! If you say you're going to be somewhere, BE THERE! If you say you feel something, MEAN IT! If you can't, won't, and don't, then DON'T LIE. Real friends keep promises and tell the truth upfront.

    They accept each other. Trying to change a person never works. A real friend is someone who truly knows you and loves you just the same.{#blank#}4{#/blank#} Be yourself and people will love the real you. If you feel like changing something about your friend, ask yourself what change you can make in yourself instead.

    They support each other's growth changes. Our needs change with time. When someone says, “You've changed,” it's not always a bad thing.{#blank#}5{#/blank#}Don't apologize for it. Instead, be open and sincere, explain how you feel, and keep doing what you know in your heart is right,

A. They keep their promises.

B. No one is happy all the time.

C. They make time for each other.

D. Don't change so that people will like you.

E. Sometimes it just means you've grown.

F. These people are your real friends in life.

G. Don't look for someone who will solve all your problems.

    Does the amount of cash in a lost wallet influence how likely a person is to return it? Classical economic theories suggest that the greater the appeal, the less likely we are to be honest—but a new study turns the idea on its head, finding altruism(利他主义), and a powerful hate for viewing oneself as a "thief" outweigh the financial attraction.

    A team of researchers conducted a huge experiment concerning 355 cities in 40 countries. More than 17,000 identical wallets were dropped off at public places, each containing a grocery list, a key, and three business cards in the local language using made-up names and an email address. Some had no money while others contained the equivalent (等值) of $13.45.

    According to the research, people on average returned 40% of wallets with no money in them but 51%with money. It also shows extreme differences between countries. But although rates of people's honesty varied greatly from country to country, one thing remained remarkably constant: wallets with money, as opposed to no money, raised reporting rates.

    In the US, the UK and Poland, they repeated the experiment with even more money: $94.15, which increased reporting rates by an average of 11% compared to the smaller amount. They also found that having a key expanded reporting rates by 9.2%.

    The findings, which run counter to a fundamental principle of classical economics, suggest honesty, altruism and self-image can sometimes be more influential than economic self-interest.

    A purely economic approach to behavior suggests people would keep the wallets with the larger amounts of money due to the increased financial reward, but economics often doesn't account for a person's sense of honesty or self-image, according to behavioral scientists. Altruism also influenced the findings, the researchers say. Since the key is valuable to the owner but not the finder, this pointed toward an altruism concern in addition to the cost of negatively updating one's self image.

    Taking good notes is a time-saving skill that will help you to become a better student in several ways. {#blank#}1{#/blank#} Second, your notes are excellent materials to refer to when you are studying for a test. Third, note-taking offers variety to your study time and helps you to hold your interest.

    You will want to take notes during classroom discussions and while reading a textbook or doing research for a report. {#blank#}2{#/blank#} Whenever or however you take notes, keep in mind that note-taking is a selective process. {#blank#}3{#/blank#}

    The following methods may work best for you.

    ● Read the text quickly to find the main facts and ideas in it.

    ● Carefully read the text and watch for words that can show main points and supporting facts.

    ● Write your notes in your own words.

    ● {#blank#}4{#/blank#}

    ● Note any questions or ideas you may have about what was said or written.

    As you take notes, you may want to use your own shorthand(速记). When you do, be sure that you understand your symbols and that you use them all the time. {#blank#}5{#/blank#}

A. Use words, not complete sentences.

B. There are three practical note-taking methods.

C. You must write your notes on separate paper.

D. Otherwise, you may not be able to read your notes later.

E. You will also want to develop your own method for taking notes.

F. That means you must first decide what is important enough to include in your notes.

G. First, the simple act of writing something down makes it easier for you to understand and remember it.