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You Can Make a Windsock(风筒)

    Have you ever seen a windsock blowing in the wind? Well, you can make one of your own! This is a fun project that you can do with things you may have. You just need to follow a few easy steps.

You will need:

●one piece of heavy colored paper   ●five ribbons

●strong tape       ●a string

●a pencil

What to do:

Step 1: Draw pictures on the paper. You can write your name on it. Do anything that will make it special to you.

    Step 2: Make the paper into the shape of a tube. Hold one of the shorter edges(边缘) over the other. Then make them together with the tape at each end and in the middle.

Step 3: Use a pencil to make a hole into both sides of the tube. The holes should be only on one end of the tube. Pull the string through both holes. Then tie the ends of the string together.

    Step 4: Now make five holes around the top of the other end of the tube.Put a ribbon through each of the holes. Tie a knot in the ends.

    Make sure the knots are bigger than the holes.

    Now your windsock is ready to use, but how does it work? The shape of the tube plays an important part. Wind blows through the tube and makes it fly and dance around. Hold the windsock up in the air by its string and run around. It will fly behind you. You can also hang it outside and watch it dance around on its own!

    What would the world be like if cars could drive themselves? Imagine seeing an empty car passing by on its way to pick up its owner, or a car full of passengers who are reading, listening to music or even sleeping. But none of them are worried about the road ahead.

    Well, all of this could be the future of driving. There are several companies, including Google, working on driverless cars. So far, no Google self-driven car has gotten a traffic ticket, bus some of them have been in accidents when other cars hit them.

    These cars are now still in the testing stages. But, if the tests are successful, these electric self-driven cars could be put into use very soon.

    The cars already have many features（特点）allowing them to take the place of drivers during certain situations. Some features include cars being able to park themselves, or slow down when they notice objects close by. They can also control the speed if there are dangerous conditions.

    Scientists and engineers believe, with the help of wireless（无线电的）signals, cameras and GPS, we are now at a stage where creating a safe self-driven car might be possible.

    The cause of deadly road accidents is usually careless drivers or dangerous conditions. The self-driven car may be able to prevent these. However, some people do not like the idea. American lawyer Whit Drake, for example, doesn't believe these cars are safe. He thinks that technologies can also be mistakes.

    Do you know what the hump(驼峰) of a camel is used for? If you answered to store water, guess again. In fact, a camel's hump is a place for storing fat.

    Most animals, including humans, store fat throughout their bodies, under their skin. But camels store their fat in one place, their hump. A hump can weigh as much as 80 pounds. Why do camels keep their fat this way? The answer is most likely because of their environment. Camels can go up to two weeks without eating because they have this fat to live off.

    Also camels are great at handling(处理，应付) changes in body temperature. Their humps can help the camels keep cooler. Their coats also help them adapt(适应) to the heat. While the coat is thick, it reflects(反射)the sunlight and protects the camel from the heat that rises off the desert sand.

    There are two kinds of camels, those with one hump and those with two humps. Camels with one hump are called Dromedary or Arabian camels. They live in the dry deserts in West Asia. Camels with two humps are called Bactrian camels. They live in Central and East Asia.

    Besides their humps, camels have a lot of interesting facts. They can live between 40~50 years. They can carry about 400 pounds and run up to 40 miles per hour. It's true that camels can go long time without drinking water, and they can drink about 26 gallons of water at a time. Camels can also close their nostrils(鼻孔). So whether a camel has one hump or two, it is one amazing animal that is very well adapted to its environment.

The Vine That Ate the South

    Kudzu is a fast-growing vine(蔓生植物) that covers a large area in the southern United States. It is so common that one might think it is a native plant, but it is not. Kudzu was brought to the United States from Japan in 1876. Many Americans thought it was beautiful, and they began to plant it. They didn't know it could grow up to a foot a day during the summer months. Nor did they know it would grow up and over anything in its path.

    In Japan, kudzu experienced cold winters and a short growing season. But in the United States, it has a very long growing season with warm and wet southern weather. It is fine weather for the vine to grow fast.

    In the 1920s, people used the vine to feed farm animals. Ten years later, the government supported to plant kudzu because it kept soil from washing away. However, by the 1950s, the government no longer wanted people to plant the vine. Twenty years after that, the government said it was a harmful plant.

    The vine grows up trees and buildings, making some beautiful shapes. However, trees die after kudzu covers them because they cannot get enough light. Scientists are looking for ways to kill the vine. They used poisons(毒药) to kill the vine. However, some of the poisons made it grow even better. Scientists also find it difficult to dig up Kudzu. The plant is really tough.

    Because kudzu is so hard to kill, some people are making the best of it. So they try to find different uses for the vine. They find the vine can be used to make paper and baskets, it can be used to feed the goats, and it can even be eaten by people. Scientists are studying it in the hope that the vine can be used as a medicine. At the very least, kudzu serves as an example of the unexpected results that can come from non-native plants.