阅读理解。

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    Fraser Island is in Queensland, Australia, about 200 kilometers north of Brisbane. It is about 120 kilometers long and 240 kilometers wide. It is a very important island because it is completely made of sand. In fact, it is the largest sand island in the world. There is no airport on the island, but there is a long beach along the east coast. Planes arrive and leave from here.

    The sand makes unusual shapes. There are hills made of sand called sandblows. Nothing grows on them. They move one or two meters a year from the northwest towards the southeast of the island, getting bigger and bigger. At other places on the island, such as Rainbow Gorge, The Cathedrals and Red Canyon, the sandy rocks have different colors. Sometimes the rocks are so brown that they turn the sea brown, like coffee.

    Surprisingly, the sandy island has a lot of different plants and animals. There are dark forests—eucalyptus woods, beautiful flowers and over a hundred lakes. There are many kinds of birds, like owls and curlews. There are many animals there, too, such as crocodiles, flying foxes and wild dogs called dingoes.

    About 500,000 people visit the island every year to see the island's beauty and nature. People enjoy camping and hiking（徒步）there. Unluckily, the visitors create problems. They damage plants and frighten animals. Their sun cream（防晒霜）makes the water dirty. So it is necessary to manage the visitors. For example, people may not use motor boats or go fishing in the lakes, and they need official papers to drive there.

     Kumar and his two friends built a robot and named it Athena. They would go for Battle of the Bots--the city's biggest robot competition, and it would start in two days. The winning team would get $5,000.

     "How are we going to beat (打败) the Cougars?" asked Alex. The Cougars was the team that won the last two years' competitions.

    Kumar said, "The Cougars always build a big and strong (强壮的) robot. But usually their robot isn't very fast."

    "Our robot is fast," Alyssa said.

    "Yes!" Kumar said. "Don't worry. I have a plan for how to do it." Kumar told the group his plan and they began to work.

    Two days later, the competition began. Kumar said to his friends, "I' m sure the plan will work and Athena will win. Just wait and see."

    Athena won all of her first battles (较量). The Cougars' big, strong robot, The Avenger, did well, too. By the end of the day, The Avenger and Athena were the only two robots left in the competition.

    Soon the battle between Athena and the Avenger began. The Avenger lunged (猛扑) for Athena, but the small robot was too quick for him. Athena went behind The Avenger and, before the larger robot had time to turn, Athena hit (攻击) him from behind. The Avenger fell" down and couldn't move.

    The three friends all jumped up excitedly. "Now it's time for the real question," said Alex“      ”

    Workers wear them. Swimmers wear them. Scientists wear them. Woodcutters wear them. People who play sports wear them. Goggles protect the eyes. They keep out water and chemicals. They keep out bits of wood or stone. They might look funny, but goggles do serious work!

    Why do people need to wear goggles? They need to keep the can hurt our eyes. Have you ever gotten a piece of sand or dirt or other small particle in your eye? What happens? It hurts. Your eye begins to fill with tears. Those tears are your body's way of getting the sand or dirt out of your eye. Sometimes this works. Your eye feels much better.

    But what happens if your tears don't work? What happens if the piece of sand has gotten stuck in your eye? Eyes are delicate. They can be scratched or cut easier than skin(皮肤). If the particle is not washed out by tears, you might have to go to the doctor. You could even have problems seeing out of that eye.

    Instead of waiting to see if tears will help, some people use goggles. This can prevent things from getting in their eyes at all. If they use goggles. Their eyes are protected from the things that can cause problems, Goggles are a better way to protect eyes. They are made of plastic or glass, and they are tied around your eye area. Some of them hook behind your ears like glasses. Other goggles have a strap (带子) that goes around your head. Both kinds stay right where you put them until you take them off. That way, you can use both hands to work or play sports, and you don t have to worry about something getting in your eyes.

    Your eyes are safe, and you can get busy working or playing!

    Robots are playing an important role in our life. They help us a lot.

    In factories, robots can help people do lots of work. They work faster and do not need a rest. People will feel bored if they do the same job again and again, but robots will not. And they can work in same dangerous places. Usually people cannot.

    In our homes, robots are useful, too. They can help us do some cooking. They can help blind people read newspapers and help the old people move some heavy things. They are our best friends. They are clean and do not need to eat food.

    However, robots are not as clever as people. They cannot think like us. If we do not "'teach" them how to do things first, they can do nothing.

    Both seasonal flu, a disease like a very bad cold, and much larger pandemics, like the one caused by H7N9（禽流感） in 2013, are the result of a race between the flu virus  and the immune system which can protect people from illness. Here's how it works.

    Viruses, which cause pandemics, have two important proteins "haemagglutinin(H) and neuraminidase(N).H helps the virus go into a cell .N helps new virus break out of that cell .They are parts of a virus that may be known and dealt with by the immune system

    A flu virus attacks a host cell in order to reproduce itself. But the virus created out of it is quite different now. The virus's genetic material is copied with low fidelity. That difference produces virus which immune system does not always know and deal with immediately. Each year's seasonal virus is therefore a little bit different, and thus requires an updated vaccine to prevent people from getting that disease.

    Pandemics viruses have bigger changes in this process .Many hosts' defences are unprepared for such big changes, which happen three or four times a century .The 1918 pandemics was caused by viruses carrying H1 and N1.Anotber two pandemics in 1957 and 1968 were caused by viruses carrying H2and H3 together with N2.They are numbered by scientists. Much of this change goes on outside humans. A flu is usually from sick binds. Sometimes a bird-flu appears with materiel that enable it to spread among people .The H7N9 is recently worrying scientists in the health center.

    The flu virus sometimes jumps directly from a bird(often a chicken) to a person, but more usually passes through a pig The cells in bird and human are built differently, It means us that the virus needs different sets of material to attack them .Pig cells have features of both so that it can act as a platform in which the virus can fit from one to the other .Even after it has made humans ill, a virus cannot go ca to cause a pandemic unless it also gets the ability to pus easily between people, Luckily, this is something H7N9 has yet to do.

How to make ice-cream in a bag

    What you need:

    I spoon of sugar, 1/2 cup of "half and half" (牛奶和奶油的混合物)，1/4 spoon of vanilla extract(香草精), d add 1 spoon of sugar, 1/2 cup of "half and half" and 1/4 spoon of vanilla extract to the small bag.

    Next, add three glasses of ice 10 the big bag. You can add more or less just to make sure that the small bag will be covered by ice.

    Then, pour about 1/2 cup of salt into the big bag. The salt helps the ice get cold so you can add more if necessary.

    When it's ready, place the small bag in the big bag and seal tightly(系紧). You need to shake the bag for about five minutes.

    Finally, take the small bag out. Be careful not to open it. Wipe off(擦去) any salt on the bag. Now open the bag. You can enjoy your ice cream. You can finish all of the work in less than ten minutes.