The Dress That Turns into a Coca Cola Machine 

    This specially designed dress looks like a normal dress，but if you unfold it and cover yourself，you may look like a Coca Cola vending machine（自动售货机）. Because there are many vending machines like that on the street，it must be easy for you to hide．If you feel that someone is following you or there is some danger，you can disappear within five seconds．But don't use it to scare your classmates．That'll be rude.
                                  

    The M-Dress is a nice black dress．It is also a mobile phone．It accepts a standard SIM card and allows the wearer to receive calls without carrying an actual(真实的) phone in their pocket or purse．You just need to bring your hand to your ear when you want to answer a phone call．When you finish talking and release your hand，the call will close．It is fashionable and useful．But it will certainly be an embarrassing moment when your dress rings in public．
  Air Conditioned Jackets 

    You will love these air-cooled jackets in summer time when it is very hot outdoors．The jacket has fans that draw air in．The fan is powered by an inside battery．Now it is possible to spend nearly every second of your day with cool air．

阅读下列短文，从每题所给的A、B、C、D四个选项中选出最佳答案。

    All living things need energy to live and grow. This energy comes first from the sun. Plants use water and sunlight to make their own food. Animals can not make their own food, and they eat plants. Other animals then eat the plant eaters.

    A food chain shows what eats what. It might show that zebras eat grass and then lions eat zebras.   

    Lions also eat other animals. Zebras eat other kinds of plants. So it takes more than one food chain to show how lions and zebras get their energy.

    A food web shows how food chains work together. From it we can see how energy moves from plants to animals.

    Plants and animals that live in hot, dry deserts depend on water as well as food. Creosote bushes have small leaves that hold water. Their seeds provide food and water for kangaroo rats. Kangaroo rats don't need to drink water. They get all the water they need from the plants they eat. Kangaroo rats keep cool by coming out only at night to look for food. Ringtail cats also come out only at night. Ringtail cats hunt and eat kangaroo rats. Coyotes eat both the kangaroo rats and the ringtail cats.

    Nothing is wasted in a food wed. Vultures eat dead animals. Vultures are scavengers. Scavengers do not hunt and kill other animals to get food. They eat animals that are already dead. When a ringtail cat or a coyote dies, it makes a meal for the vultures. Scavengers do an important job in keeping the environment clean.

    Waste can be seen everywhere in the school. Some students ask for more food than they can eat and others often forget to turn off the lights when they leave the classroom. They say they can afford these things. But I don't agree with them.

    Waste can bring a lot of problems. Although China is rich in some resources(资源), we are short of others, for example, fresh water. It is reported that we will have no coal(煤) or oil to use in 100 years. So if we go on wasting our resources, what can we use in the future and where can we move? Think about it. I think we should say no to the students who waste things every day. Everybody should stop wasting as soon as possible.

    In our everyday life, we can do many things to prevent waste from happening, for example, turn off the water taps when we finish washing, turn off the lights when we leave the classroom, try not to order more food than we need, and so on. Little by little, everything will be changed. Waste can be stopped one day, if we do our best.

    We know people can be nice, but what about animals?

    Scientists say that some animals are capable(有能力的)of being nice. Animals that live in groups-like foxes, chimpanzees(大猩猩), and elephants-follow rules. They have to follow rules to get along and to survive(生存). However, animals can act nicely, even when they don't have to. Here are some surprising stories about animal behavior.

    Most people usually walk away when someone is unkind to them. Marc Bekoff, a researcher at the University of Colorado, saw a female(母的)red fox do just that. The female fox was unhappy because a male(公的)fox played roughly(粗鲁地)with her. When she walked away, the male fox showed her that he wanted to play nicely. He lowered his head and rolled on his back. The female fox gave him another chance, and this time, he played more gently.

    Geza Teleki is a scientist who studies chimpanzees in Tanzania. One day, Teleki hiked far away from his campsite. He didn't have any food. Teleki wanted some fruit from a tree, but the tree was too tall. A young chimpanzee watched him curiously as he tried to get something to eat. The chimpanzee climbed the tree, picked the fruit, and gave it to him!

    An elephant in Kenya hurt his trunk(象鼻子). He needed help because he couldn't put food into his mouth. Researcher Kayhan Ostovar watched silently. He saw the hurt elephant show his sore trunk to a healthy elephant. The healthy elephant didn't need any more information. He took a bush and put it carefully into his new friend's mouth.

    Hippos(河马)and crocodiles are usually good friends. They hang out together in rivers. But Karen Paolillo, a wildlife expert in Zimbabwe, saw something surprising. One day, a crocodile tried to eat a monkey that was next to a river. A hippo ran quickly to the crocodile and chased it away. Why did the hippo attack(攻击)the crocodile? Paolillo says hippos sometimes protect other animals from crocodiles.

    There are some easy things you can do to protect the earth:

    •Plant flowers, grass or trees.

    •Whenever you visit a park or beach, take away what you take there. Keep rubbish in a bag until you can put it in a dustbin (垃圾桶).

    •Turn off the lights and TV set when you leave the room. This can save a lot of electricity.

    •Turn off the tap when you brush your teeth. You can save some water by not letting it run. Also, use a glass cup instead of a paper cup because this saves paper.

    •Give your old books and magazines to a library instead of throwing them away.

    •Give your old clothes to poor children you know instead of throwing them away.

    •Use both sides of paper.

    •Stop pouring dirty water into the rivers or lakes nearby.

    •Encourage all your friends to do the same things you do to help protect the earth.

    You don't have to wait until Earth Day to do these things. Make every day Earth Day. If everyone makes a contribution (贡献) to protecting the environment, the earth will become much more beautiful.

    If you look at the top of your phone, you'll usually see a little symbol that says 3G or 4G.The "G" stands for the "generation (代)" of your mobile phone network. But these symbols will become things of the past after 5G networks fully arrive.

    On March 30, Shanghai vice-mayor Wu Qing made the first 5G video call on a Huawei Mate X smartphone, CGTN reported. Shanghai has also become the first city in China to start testing 5G networks.

    About 100 times faster than 4G networks, 5G will let people download and upload data faster than ever before. But 5G won't just bring faster mobile Internet. People can use it to do many other things as well.

    For example, 5G will help to make self-driving cars safer. Today's self-driving test cars have one problem-lag (延迟). When the car "sees" an obstacle (障碍物), it sends he information to a data center and receives instructions. However, it takes time to send and receive the information with this kind of lag, the cars might crash because they don't receive instructions in time. With 5G, this lag will be greatly lowered, making the cars safer according to CNN.

    5G could also be used to power the Internet of Things (IoT). This means a large online network that connects all things and people. Fast Internet speeds will be the key to developing this technology. The IoT could be used in a lot of ways. For example, with IoT, your fridge could automatically (自动地) place an order online for eggs when it finds that there are no eggs left.