Sports can help you keep fit and get in touch with nature. However, whether you are on the mountains, in the waves, or on the grassland, you should be aware that your sport of choice might have great influence on the environment.

    Some sports are resource-hungry. Golf, as you may know, eats up not only large areas of countryside, but also tons of water. Besides, all sorts of chemicals and huge amounts of energy are used to keep its courses（球场） in good condition. This causes major environmental effects. For example, in the dry regions of Portugal and Spain, golf is often held responsible for serious water shortage in some local areas.

    There are many environment-friendly sports. Power walking is one of them that you could take up today. You don't need any special equipment except a good pair of shoes; and you don't have to worry about resources and your purse. Simple and free, power walking can also keep you fit. If you walk regularly, it will be good for your heart and bones. Experts say that 20 minutes of power walking daily can make you feel less anxious, sleep well and have better weight control.

    Whatever sport you take up, you can make it greener by using environment-friendly equipment and buying products made from recycled materials. But the final goal should be "green gyms". They are better replacements（代替物）for traditional health clubs and modern sports centers. Members of green gyms play sports outdoors, in the countryside or other open spaces. There is no special requirement for you to start your membership. And best of all, it's free.

    Of the many unpleasant emotions we can experience, fear may top the list. {#blank#}1{#/blank#}. Fear can also keep us from pursuing the things in life that really matter — like following our dreams, and developing important relationships. I have some ideas, though, of how to be free from fear.

Experience fear.

I used to be very afraid of speaking in front of people. I would get sweaty palms and my stomach would be so tied up that I wouldn't be able to eat. However, each time I spoke, I noticed afterwards that it wasn't that bad. Things I fear are never as bad in reality as I make them out in my mind. {#blank#}2{#/blank#}.

Create space.

    The first and most important step to being fearless is to create some space between ourselves and the emotion of fear. This isn't accomplished by ignoring the fear, or trying to talk ourselves out of it. {#blank#}3{#/blank#}. In fact, a recent research shows that by simply admitting the emotion we actually begin to reverse the "fight or flight(逃避)" response in the body.

Control the breath and feel the fear.

    Once we acknowledge the presence of fear, the second step is to control the breathing so that it becomes slower and gentler. We try to make the breath just a little bit longer, and feel how fear manifests(展现) in the body. {#blank#}4{#/blank#}.

    With practice, we can create enough space between us and the emotion of fear so that we're able to replace a fearful thought with a positive one. {#blank#}5{#/blank#}. For instance, before I get up to speak in front of a group of people, I imagine that the audience is positively impressed by what I say and that I manage to complete the speech successfully.

    Science fiction writers create imaginary worlds. The way things work in your imaginary worlds will be based on actual science. So it's important for you to be familiar with the scientific principles and inventions that are related to your creation. For example, if you're writing about human living on a planet with zero gravity, then you need to know the effects of zero gravity on the human body.

    Then you have to figure out the exact rules of your imaginary worlds. And you have to follow them. If humans are able to breathe underwater in Chapter 1, your character can't drown in a swimming pool in Chapter 3. The issue here is maintaining your readers' trust. That means the readers are willing to pretend along with you. If you start out with an ordinary detective novel and then throw in someone breathing underwater in the 6th chapter, you will pull the readers out of their imagination. The same thing happens if you change the rules halfway.

    Part of your preparation work for the novel is to map out its worlds in great detail. You should decide the following issues: the history of the world, the geography, what possibilities it offers, how everything works in this new reality, and how all of these factors affect the way your characters think, feel, and react to things. You don't have to tell your readers all the rules in the first chapter. But you have to let readers know enough to understand what's going on. This also allows you to work out logical problems and contradictions before you start writing.

    When you are writing, remember to make it feel real. You are inviting readers to visit a new world. They will want to be able to see, hear, feel, smell, and even taste what it's like. Whether your novel is about a world without disease or an undiscovered planet, help your readers feel like they're actually there.

    The first organized system for sending messages began in Egypt around 1500 B.C. This system developed because the pharaohs frequently needed to send messages up and down the Nile River in order to keep their empire running smoothly. Later, the Persians developed a more efficient system for sending messages using men and horses. Messages carriers rode along the road system stretching from one end of the Persian Empire to the other. Along these roads, fresh men and horses waited at special stations to take and pass along any messages that needed to be sent. The stations where riders passed messages back and forth were built 23 kilometers apart, so the men and horses were able to travel quickly between them. The Romans later took up his idea and improved it by using a more advanced and extensive road system.

    In China, however, Kublai Khan had built up his own system for delivering messages. This system worked in the same basic way as the Roman system. The difference was that Kublai Khan kept 300,000 horses along the roads of this delivery lines. There were over 10,000 stations where a message would be passed from one rider to another with a fresh horse. In this way, Kublai Khan could receive messages from anywhere in the country in only a few days.

    It was not until the 1500s that a well-organized postal system appeared again in Europe. One family, the von Taxis family, gained the right to deliver mail for the Holy Roman Empire and parts of Spain. This family continued to carry mail, both government and private, throughout Europe for almost 300 years.

    In 1653, a Frenchman, Renouard de Velayer, established a system for delivering post in Paris. Postal charges at that time were paid by the recipient, but de Velayer's system was unique by allowing the sender to pre-pay the charges, in a similar way to the modern stamp. Unfortunately, de Velayer's system came to an end when jealous competitors put live mice in his letter boxes, ruining his business. Eventually, government-controlled postal systems took over from private postal businesses, and by the 1700s government ownership of most postal systems in Europe was an accepted fact of life.

    The thing that all these early systems had in common was that they were quite expensive for public use, and were intended for use by the government and the wealthy. However, in 1840, a British schoolteacher named Roland Hill suggested introducing postage stamps, and a postal rate based on weight. This resulted in lowering postal rates, encouraging more people to use the system to stay in touch with each other, His idea helped the British postal system begin to earn profits as early as 1850. Soon after that many other countries took up Mr. Hill's idea. And letter writing became accessible to anyone who could write. Today, the Roland Hill awards are given each year to "encourage and reward fresh ideas which help promote philately"(stamp collecting).

    For many students who desire to move around but not far freely, one of the most common vehicles is the bicycle. For such a seemingly simple invention, its story is not that simple.

    Most historians trace its origin back to 1817, when a German nobleman named Karl von Drais invented a wooden, two­wheeled machine that riders moved forward with their feet. His invention became popular in both England and France, where it eventually became known as the velocipede. Unfortunately, it was eventually banned as a danger to pedestrians and was rarely seen after the early 1820s.

    Things were quiet for several decades until the bicycle development took off in the 1860s. An important milestone happened in Paris in 1863 when pedals were added to the front axle (轴). This occurred in Pierre Michaux's workshop, but it's unclear whether he or his employee, Pierre Lallement, should be given credit for the innovation Lallement moved to the United States, where he obtained a patent for "improvements in velocipedes" in 1866. These new machines proved to be popular, and the name "bicycle" had come into use by 1869. However, many people referred to them as "bone shakers", which described their clunky ride due to a heavy wooden frame and steel wheels.

    In the 1870s, "high wheelers" or "penny­farthings" became popular. However, with a large front wheel and a much smaller rear wheel, they could be dangerous, if riders had to stop suddenly, as they would "take a header" when their momentum (动量) carried them over the front wheel onto their heads. Eventually, English inventor John Kemp Starley designed a "safety bicycle" with two same small wheels, a chain drive, and a set of gears. With tires added in and brake systems bettered in the following decades, bicycle production had skyrocketed to over one million bicycles by 1899.

    Mass production of bicycles increased their popularity greatly, since they became affordable for the average person. Over the course of the 20th century, manufacturers continued to improve the features and design of bicycles as new technologies appeared.

Tricks to become a patient person

Here's a riddle: What do traffic jams, long lines and waiting for a vacation to start all have in common?{#blank#}1{#/blank#}. They're all situations where we could use a little extra patience.

In the digital age, we're used to having what we need immediately and right at our fingertips. However, research suggests that if we practiced patience, we'd be a whole lot better off. Here are several tricks.

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

Thankfulness has a lot of benefits. {#blank#}3{#/blank#}. It can also help us practice more patience. "Showing thankfulness can foster self-control," said Ye Li, researcher at the University of California.

Make yourself wait

Instant gratification (满足) may seem like the most "feel-good" option at the time, but psychology research suggests waiting for things actually makes us happier in the long run. And the only way for us to get into the habit of waiting is to practice. Start with small tasks. {#blank#}4{#/blank#} or wait 10 extra minutes before going for that cake. You'll soon find that the more patience you practice, the more you start to apply it to other, more annoying situations.

Accept the uncomfortable

{#blank#}5{#/blank#}. When we experience something outside of our comfort zone, we get impatient about the circumstances. You should learn to say to yourself, "This is merely uncomfortable, not intolerable (无法忍受的)." You'll then gradually become more patient.

A. There is one answer

B. Keep a balanced state of mind

C. Practice showing or expressing gratitude

D. Attach importance to process and method

E. Put off watching your favorite show until the weekend

F So many of us believe being comfortable is the only state we will enjoy

G. Research shows it makes us happier, less stressed and even more optimistic