E

    The Earth is our home; we must take care of it. This means keeping the land, air and water clean. Pollution is a dirty word. To pollute means to make things unfit or unclean to use. Pollution comes in many ways. We see it, smell it, taste it and drink it. Pollution is beginning to threaten (威胁) our health, our happiness and our life. Man has been polluting the earth from the time he first made fire, washed his clothes in the river and threw his waste on the ground. When land was used up or water became dirty, men moved on to another place. At first, the problem was not so serious because there was plenty of clean air, land and water. There weren't so many people then and their wants were fewer. All the dirty things could be absorbed (吸收) by nature and soon covered over. But this is no longer true. The increase of population and the development of industry(工业)have changed that. Man is slowly poisoning (毒害) his environment. Through the use of poison, man has polluted the land, killing the animals. By putting dirty water and chemicals into rivers and lakes we have polluted our drinking water, killing the fish.

    Our increasing population is part of the problem. More people, more waste.

    Where is this all to end? Are we turning the world into a big rubbish dump (堆存处), or is there any hope that we can get rid of (摆脱, 除去) the pollution? Luckily, millions of people have been warned of the danger of pollution. Large numbers of people are now working hard to bring pollution under control.

    Stop reading for a minute and think about what you see when you look up at the sky on a clear night. You probably see many stars (星星). Long long ago, farmers watch some stars to know when to plant their crops. Travelers did so to find their way in the dark. Today stars are still important to some people.

    Scientists find that most stars are very big. In fact some stars are so far away that it would take millions of years to get to them even by spaceship.

    Another thing we know today about stars is that some are made up of(由…组成) hot gases. The gases are so hot that they send out light. If you watch a star carefully, you may notice that it twinkles(闪烁)sometimes. As you may understand, light from a star must shine through the air before you can see the star. Air is always moving, it makes light from the star move back and forth. When the light moves, it makes the star twinkle. Stars also have different colors. The colors of a star depend on how hot it is. To our surprise, the cool stars are red and the hottest stars are white.

    Techeng Island(特呈岛)lies in the southeast of Zhanjiang. The villagers there used to make a living by fishing. But now, most of them make much money by doing business. They believe that their island is a gift from nature and they give thanks to it every day. In 2003, President Hu Jintao came to visit the island and pointed out that the government of Zhanjiang should take the is land into a "civilized new ecotourism island"(文明生态旅游新海岛). Since then, the island has opened a new page in history.

    Today, the island has become a popular place for tourists. It takes you about 15 minutes to get there by boat from Maxie Pier(码头)near Haibin Park. But it is a just 8­minute boat ride from Zhanjiang Port Pier. In the resort(度假村), you can not only enjoy the fantastic sights but also have a lot of interesting things to do, like walking on the beach, visiting the museum and enjoying the delicious seafood. The best way to relax yourself is to enjoy the hot springs(温泉)there.

    Welcome to Techeng Island! It's a place to visit!

    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.