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Population Change

    Why is the world's population growing？The answer is not what you might think. The reason for the explosion is not that people have been reproducing like rabbits, but that people have stopped dropping dead like flies. In 1900,people died at the average age of 30.By 2000 the average age was 65.But while increasing health was a typical feature of the 20^th century, declining birth rate could be a defining one of the 21^st.

     Statistics show that the average number of births per woman has fallen from 4.9 in the early 1960s to 2.5 nowadays. Furthermore, around 50% of the world's population live in regions where the figure is now below the replacement level(i.e.2.1 births per woman)and almost all developed nations are experiencing sub-replacement birth rate. You might think that developing nations would make up the loss(especially since80% of the world's people now live in such nations),but you'd be wrong, Declining birth rate is a major problem in many developing regions too, which might cause catastrophic global shortages of work force within a few decades.

     A great decline in young work force is likely to occur in China, for instance. What does it imply? First, China needs to undergo rapid economic development before a population decline hits the country. Second, if other factors such as technology remain constant, economic growth and material expectations will fall well below recent standards and this could invite trouble.

     Russia is another country with population problems that could break its economic promise. Since 1992 the number of people dying has been bigger than that of those being born by a massive 50%,Indeed official figures suggest the country has shrunk by 5% since 1993 and people in Russia live a shorter life now than those in 1961.Why is this occurring? Nobody is quite sure, but poor diet an above all long-time alcoholism have much to do with it. If current trends don't bend. Russia's population will be about the size of Yemen's by the year 2050.

     In the north of India, the population is booming due to high birth rates, but in the south, where most economic development is taking place, birth rate is falling rapidly. In a further twist, birth rate is highest in poorly educated rural areas and lowest in highly educated urban areas. In total,25% of India's working-age population has no education. In 2030,a sixth of the country's potential work force could be totally uneducated.

    One solution is obviously to import foreign workers via immigration. As for the USA, it is almost unique among developed nations in having a population that is expected to grow by 20% from 2010-2030,Moreover,the USA has a track record of successfully accepting immigrants. As a result it's likely to see a rise in the size of its working-age population and to witness strong economic growth over the longer term.

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    The Internet has opened up a whole new online world for us to meet, chat and go where we've never been before. But just as in face to face communication, there are some rules of behavior that should be followed when on line.

    {#blank#}1{#/blank#} Imagine how you'd feel if you were in the other person's shoes. For anything you're about to send，ask yourself, ＂Would I say this to the person's face?＂ If the answer is no, rewrite and reread.{#blank#}2{#/blank#}

     If someone in the chat room is rude to you, your instinct (本能) is to fire back in the same manner. But try not to do so. {#blank#}3{#/blank#} If it was caused by a disagreement with another member, try to fix the situation by politely discussing it. Remember to respect the beliefs and opinions of others in the chat room.

    {#blank#}4{#/blank#} Offer advice when asked by newcomers, as they may not be sure what to do or how to communicate. When someone makes a mistake, whether it's a stupid question or an unnecessarily long answer, be kind about it. If it's a small mistake, you may not need to say anything. Even if you feel strongly about it, think twice before saying anything. Having good manners yourself doesn't give you license to correct everyone else. {#blank#}5{#/blank#} At the same time, if you find you are wrong, be sure to correct yourself and apologize to those that you have offended. It is not polite to ask others personal questions such as their age, sex and marital status. Unless you know the person very well, and you are both comfortable with sharing personal information, don't ask such questions.

    It's normal to wake briefly during the night. {#blank#}1{#/blank#}But if you're waking up during the night and having trouble falling back asleep, the following tips may help.

    Stay out of your head. The key to getting back to sleep is continuing to prepare your body for sleep, so remain in bed in a relaxed position. Hard as it may be, try not to stress over the fact that you're awake , because that very stress and anxiety encourage your body to stay awake. {#blank#}2{#/blank#}

    {#blank#}3{#/blank#} If you are finding it hard to fall back asleep, try a relaxation technique such as visualization, deep breathing, or meditation, which can be done without even getting out of bed. Remind yourself that although they're not a replacement for sleep, rest and relaxation still help refresh your body.

    Do a quiet, non-stimulating activity. If you've been awake for more than 15 minutes, try getting out of bed and doing a quiet, non-stimulating activity, such as reading a book. Keep the lights dim so as not to think that it's time to wake up. {#blank#}4{#/blank#} A light snack might help relax you, but be careful not to eat so much that your body begins to expect a meal at that time of the day.

    {#blank#}5{#/blank#} If you wake during the night feeling anxious about something, make a brief note of it on paper and postpone worrying about it until the next day when you are fresh and it will be easier to resolve.

    Please Don't Be Afraid To Travel On Your Own

    You want to travel. You make an unclear plan. {#blank#}1{#/blank#} But either way, you're leaving in six months time. You start doing research every single night.

    Of course, as this will be your first ‘real' travel experience, you naturally prefer to travel with other people. {#blank#}2{#/blank#} But the first friend you ask, perhaps your closest friend, turns you down and so you move on to the next friend. {#blank#}3{#/blank#} The third friend, the fourth friend and even that guy that you don't really like say no as well.

    {#blank#}4{#/blank#}You hope that one of your friends will change their mind and decide to join you. Maybe you decide to forget about your trip altogether, fully believing that you can only travel so far away from home with a friend or travel companion (同伴) by your side.

    Don't give up just yet. Here's my advice to you. You may be on your own when you board that flight to Bangkok or Mexico City, but believe me, once you arrive, you'll never actually be alone. That's how travel works. Unless you stare at the ground and never talk to anyone, you're going to meet people when you travel, lots and lots of people from all over the world. {#blank#}5{#/blank#}

A. Don't give it up.

B. Maybe you'll fly to Thailand or to Mexico.

C. Meeting new people is one of the worst things to do.

D. But they too, tell you they have no interest to join you at all.

E. They will be interested in meeting and hanging out with you.

F. So you start asking your friends to join you in your journey.

G. Maybe you decide to put off your trip for another six months.

    Many people know that trash is a big problem on planet Earth. What many people don't know is that trash has become a problem in outer space too. {#blank#}1{#/blank#}

    Statistically, there are more than 22,000 pieces of junk in space around the earth. And these are just the items that we can see from the surface of the earth by telescopes or radars. {#blank#}2{#/blank#}

    Objects, like bits of old space rockets or satellites, move around the planet at very high speeds, so fast that even a very small piece can break important satellites or become dangerous to people, particularly astronauts. If the tiniest piece of junk crashed into a spacecraft, it could damage the vehicle. That's because the faster an object moves, the greater the impact if the object collides with something else.

    To help minimize additional space junk, countries around the world have agreed to limit the time their space tools stay in orbit to 25 years. Each tool must be built to fall safely into the earth's atmosphere, or the mass of gases that surround the earth, after that. {#blank#}3{#/blank#}

    Many scientists are also proposing different ways to clean up space junk. The Germans have been planning a space mission with robots that would collect pieces of space trash and bring them back to Earth so that they can be safely destroyed.

    "In our opinion the problem is very challenging, and it's quite urgent as well," said Marco Castronuovo, an Italian Space Agency researcher who is working to solve the problem. {#blank#}4{#/blank#} Many of these objects are tools that help people use their cell phones or computers.

    "The time to act is now; as we go farther in time we will need to remove more and more fragments," he says.

A. One reason that it's urgent is that countries are sending more and more objects into space.

B. There are also millions of smaller pieces of junk that we can't see.

C. Blowing up older satellites with a missile may create thousands of smaller pieces!

D. In the upper parts of the atmosphere, it will burn up.

E. When two objects in space collide, the two objects break into many smaller pieces.

F. Years of space exploration have left tons of "space junk" in orbit around the planet.

    Confidence (自信) is very important in daily life. It can help you to develop a healthy attitude (态度). A study shows that the people who are more confident are much happier. They can have more chance to make themselves successful. When you are not confident you can't do well what you want to do. But how to be more confident? Here are some suggestions:

    Speak loud   You speak in a voice so low that other people can hardly hear you. Try to speak loud enough so that people can hear you clearly. The high voice can help you become more confident.

    Play sports   Physical exercise makes you tired but completely relaxed. A strong body helps you be full of confidence.

    Encourage yourself   Write down a list of things you did during the day to see how many things you have done well. Did you finish your homework? Did you tell a joke that made everybody laugh? Give yourself praise for the good things you've done.

    Get rid of (消除) fear   Fear comes along with failure (失败). But it's easy to overcome (克服) if you know that failure is part of your life. Don't hide your head just because you said something stupid last time. Try to start again and believe you can do better.

    Pick up a hobby   If you like singing, sing as much as you can. In some ways, a hobby can make you outstanding. And it will make you happy and confident.