Free energy is everywhere around us. There are many ways to make and collect energy from various sources like sun, wind and water. People also realize that everyday stuff can be a source of energy too. For example, riding a bike, running or just walking, etc. We simply have to change our way of thinking if we want to change the world.

    So comes the idea of solar roadways. Are they the road of future? Why use roads just for driving and collecting tolls (过路费)? Why don't we use them for collecting energy?

    The US Department of Transportation recently awarded $100,000 to Solar Roadways to build the first ever Solar Road Panel. So how do these future roads work?

    The Solar Road Panels will contain embedded (嵌入的) LEDs which “paint” the road lines from beneath to provide safer nighttime driving as well as to give drivers instant instructions such as detour (绕行) ahead. The road will be able to sense wildlife on the road and can warn drivers to “slow down”. There will also be embedded heating elements in the surface to prevent snow and ice buildup, providing safer winter driving.

    Replacing asphalt (沥青) roads and parking lots with Solar Roadway Panels will be a major step toward stopping climate change. Fully electric vehicles will be able to recharge along the roadway and in parking lots, finally making electric cars practical for long trips.

    We just can't wait to see more of these roads all over the world in the near future.

    Sharpshooters refer to those who are skilled at firing a gun and accurately hitting what they are aiming at. However, some fish are also called amazing sharpshooters. People wonder how they hit their targets without using tools? By spitting! The fish shoot so accurately that they rarely miss their target.

    These amazing fish are archerfish (印度射水鱼).There are several different types of archerfish living in Southeast Asia. They spit at their dinner to catch it. To catch dinner, a fish first sets itself in a certain place, for example just below the surface of the water. It puts the tip of its mouth so it barely breaks through the water. Then, the fish waits for an unsuspecting insect to land on a leaf or branch hanging over the water.

    When an unsuspecting, or unknowing insect lands, the fish attacks. The fish squeezes its gill (腮)covers very rapidly, which forces water into the fish's mouth. In the roof of its mouth the fish has a groove (槽）. The fish forms the small groove and its tongue into a narrow tube by pressing its tongue up against its groove. The water forced into the fish's mouth is forcefully pushed out of the fish's mouth through the tube. Archerfish have been known to send a stream up to 5 meters (16 feet). However, archerfish can only shoot insects up to 1-2 meters (3-6 feet) away due to their limited accuracy.

    When the unsuspecting insect is hit with a sudden stream of water, it is knocked into or falls into the water. Once in the water, the insect becomes dinner. Archerfish learn how to spit when they are young. They get more accurate with practice. Adult archerfish rarely miss.

    Within a meter, archerfish will often spring out of the water and grab an insect in their mouths.

    In our annual Readers' Choice Awards survey, we asked our readers to rate their favorite cities in the world for arts and culture. These cities are centers of music and dance, museums, and theaters. Here are four of them where you can find inspiration in the arts, starting with the top spot.

    Rome, Italy

    At its peak, the Roman Empire extended over nearly two million square miles of land across Europe, Asia Minor and North Africa. Today, that history is on display everywhere. The city's main attractions are famous not because of tourist advertisements, but because they are really so impressive. No wonder it's known as the Eternal City: You could spend forever here and find new artistic and cultural treasures every day.

    Paris, France

    Hemingway famously called Paris "a moveable feast", but wherever you go while in the city, there is always something to see, hear, taste or feel. With some 150 museums, Paris doubles as an art history class, offering the very best of the discipline across centuries and styles.

    London, United Kingdom

    London is inspiration and setting for the rise of Shakespeare, Dickens, Orwell and Eliot and the breeding ground for all those iconic (标志性的) bands: The Kinks, The Clash and The Stones. London is also Banksy's favorite canvas, home to more than 1,000 galleries, and the kind of place where you can spend a whole day in a single museum and still be ready for more when it opens the next morning.

    Vienna, Austria

    As we all know, Western music would be unrecognizable without Austria's capital, which nurtured many famous musicians. It's also the site of the Vienna Secession, a revolutionary art movement founded in 1897 by Gustav Klimt. Visitors today can see the fruits of all that creativity in the city's 100 – odd museums.

The United Kingdom has several names and many people {#blank#}1{#/blank#}（confuse) by them. In the 16th century, the nearby country of Wales was joined to the Kingdom of England. Later,the country Scotland and the Kingdom of Ireland joined the country {#blank#}2{#/blank#}（form) the United Kingdom of Great Britain and Ireland.

{#blank#}3{#/blank#}（final) , in the 20th century,the southern part of Ireland broke away from the United Kingdom, {#blank#}4{#/blank#}resulted in the full name today:the United Kingdom of Great Britain and Northern Ireland.

The four countries {#blank#}5{#/blank#} (belong) to the United Kingdom work together in some areas. They use the same flag, {#blank#}6{#/blank#}(know) as the Union Jack, as well as share the same currency and military defence. However,there are some {#blank#}7{#/blank#}（different)between them.

The United Kingdom has a long and interesting history to explore,which can help you learn more about the country and its traditions. Wherever you go in the UK,you are surrounded {#blank#}8{#/blank#}evidence of four different groups of people who took over at different times throughout history.

The first group, the Romans, came in {#blank#}9{#/blank#}first century. Some of their great achievements included building towns and roads. Next,the Anglo-Saxons arrived in the fifth century. They introduced the beginnings of the English language. The Vikings came in the eighth century, left behind lots of new vocabulary. The last group were the Normans. They had castles {#blank#}10{#/blank#} (build) all around England,and made changes to the legal system.