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    Hippos(河马) live in Africa(非洲). They are one of the world's largest land animals. Here are some interesting facts about them.

●Where are hippos born?

    Hippos often give birth in the water. The hippo babies get out of water right after birth to take their first breath.

●How quickly do hippos grow up?

    Hippo babies nurse both under water and on land for a year. Then they stop taking their mothers' milk but they are still with their mothers until they are eight years old. Then they move out.

●What do hippos love?

    Hippos love water and they spend most of the day in it to stay cool. The Hippo can breathe, see and hear when its body is under water because its nose, eyes and ears are on the top of its head.

●Do hippos swim better than people?

    Yes, they are great swimmers and they can hold(屏住) their breath for five minutes. Hippos can even walk under water along the bottom(水底) of rivers and lakes.

    Each year more than2,500 people die and 12,600 are injured in home fires just in the UnitedStates, with direct property(财产) lossbecause of home fires at about $7.3 billion every year. Every day Americansexperience tile horror(惨状) of fires, but most people don'tunderstand fires.

    To protect yourself, itis important to learn something about home fires.

    In less than 30 secondsa small flame can get completely out of control and turn into a major fire. Itonly takes minutes for thick black smoke to fill a house or for it to be inflames. Most deadly fires occur in the home when people are asleep, lf yourealize a fire, you won't have time to take valuables because the fire spreadstoo quickly and the smoke is too thick. The fire uses up the oxygen you needand produces smoke and poisonous(有毒的) gases that kill. Breathing even small amounts of smoke and toxicgases can make you tired and sleepy, and short of breath. The smoke can causeyou to be a deep sleeper before the flames reach your door. You may not wake upin time to escape.

    Room temperatures in afire can be 100 degrees at floor level and rise to 600 degrees at eye level.Breathing in this super-hot air will burn your lungs. It can melt clothes toyour skin. In five minutes, a mom can get so hot that everything in it startsto burn at once.

    Fires are bright atfirst, but quickly produce black smoke and complete darkness. If you wake up toa fire you may be blinded, confused about where you are or which direction you shouldgo in and unable to find your way around the home you've lived in for years.

    Only when we know thetrue nature of fires can we prepare our families and ourselves.

    I am a little lion. My name is Nancy. I have a big head. I'm yellow. But my favorite colour is green. I like living in the forest. I like to eat little animals. But I live in the zoo now. I don't like the zoo. I get up in the cage（笼子） in the morning. I have breakfast, lunch and dinner in the cage. I go to bed in the cage in the evening, too. People watch me every day. Some boys hit（打） me with stones（石头）. I don't like them. They are not my friends. I can't go out. I want to go back to my friends in the forest. I want to live with them.

    Have you ever wished that your life was like a reality TV show(真人秀节目)? Well, like it or not, things might be this way in the future.

    This is because of Google glasses. Glasses are the latest technology from Google. They have more exciting features(特征)than you could possibly imagine.

    For one thing, people who wear the glasses can shoot videos and record the sounds around them. So if your friend is wearing Google glasses, he or she can record your every move and broadcast live on the Internet for the world to see.

    There is a GPS system in the glasses. So if you get lost you can say" OK, Glass, where am I?", and it will find where you are and tell you where you need to 90.

    Google glasses are a bit like a helpful secretary. You can tell them what you want to write in an e—mail and they will type it for you.

    Since April 16, Google glasses have been on the market in small numbers. But by the end of the year anyone will be able to buy a pair for about 2, 500 yuan.

    Some people are not sure whether they find Google glasses cool or not. When someone is wearing Google glasses, it is not easy to see whether or not they are using them.

    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 lite symbol that says 3G or 4G. The "G" is the generation(代)" of your mobile network (移动网络). But these symbols will become things of the past after 5G networks fully arrive.

    On March 30, 2019, Shanghai vice mayor (副市长) Wu Qing made the first SG 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 (下载) and upload data (数据) faster than ever before. But 5G won't just bring faster mobile internet. People can use it for 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 this information to a data center and receives instructions (指令).

    However, it takes time to send and receive this information. With this kind of lag, the cars might hit each other because they don't receive instructions in time. With 5G, this lag will be greatly lowered (降低), making the cars safer, according to CNN. 5G could also be used to help the internet of things (IoT,物联网). IoT is a large online network that connects all things and people. Fast internet speed will be the key to developing this technology. The IoT could be used in a lot of ways. For example, with IoT, your refrigerator could automatically (自动地) place an order online for eggs when it finds that there are no eggs left inside.