Traveling（旅行) is one of the most important activities and people were interested in it many years ago. Modern traffic develops(发展) fast, so traveling to different places has become much faster than before.Staying healthy while traveling can make your trip happier. But do you know how to keep healthyduring a trip? The following advice may be useful to you.

    Before leaving

①Wear comfortable shoes, a hat and sunglasses.

②Take some medicine that you need with you. They can be used when you get ill or have other problems.

③Do some exercise for weeks or months before you leave if you plan to do lots of walking or climbing during your trip.

④Prepare（准备） proper (适当的)food. Take bread, biscuits and some fruit for a long time. They don't go bad quickly. Bring meat, fish, eggs, milk and even salads and vegetables for a nearer one.

While traveling

①Be sure not to eat dirty food or bad fruit.

②Have enough time to take a rest during your trip.Itcan help you become more relaxed.

③Tap（水龙头）water is not safe, so drink bottled water and always clean the cover of the bottle.

④Keep food in good condition（状态）. Remember: If you travel with food, keep hot food hot and cold food cold.

B

    In 2017, when the high speed train. Furing, left Beijing for shanghai at a speed of 350 km/h, it amazed the world. It is China's newest high-speed train and also the fastest train in the world.

    There were 2, 959 high-speed trains running across China by 2016. They make up60 percent of the world's total high- speed trains. Chinese companies have also built more than 10 high-speed railways in Europe, Southeast Asia and South America. And the high speed trains has become a new name card for China.

    Besides the high-speed trains, many other innovations(创新)have also changed people's lives in China.

    For example, though bike sharing is not new itself China has made it much more convenient. And popular. When the Chinese bike sharing companies reached Singapore and Britain months ago, users there excited and couldn't wait to post photos of themselves riding the bikes on social media(媒体).

    Cashless payment has become a lifestyle choice in China it is common that people in China go shopping with no cash(现金)in pockets. Many people just pay with their bile phones by scanning a quick respond code(QR，二维码)from the seller. Even a person selling vegetables has a QR code.

    Many foreigners have experienced lives without carrying any cash in China. They say they can't do it when they are back home in Europe.

    China is now in a great time. It has made great achievements in innovation. They are true pictures of national strength. It seems that China is really leading in some ways. And Chinese people have every reason to believe in an even brighter future.

    Today is December 15, 2030. Influenced by the launch of the first manned mission to Mars next month, you will most likely get a gift card for a space trip.

    The interest in trips, 100km above the surface of the Earth, has grown steadily since such a trip began. However, the market has grown much larger this year since the official announcement of the Mars mission. More low - cost spacelines have entered the market and you can now find flights for such a trip for as low as $3,495.It's very reasonable.

    Space tourism( 旅游业，观光业) is one of the markets that have developed fast during the last decade, with the opening of the Starbright Hotel on the moon as well as the low orbital hotels that started accepting guests. However, accommodation in space is still expensive for the average household, so the suborbital (亚轨道的) flights with thirty - minute weightlessness during the three - hour flight will for some time be the most popular trip.

    However, the spacelines might in the future face fierce competition between space elevators (太空升降舱), like the one that is projected to start construction within two years. Once it is fully functional, it will start to ship cargo to space. But it will accept passengers as soon as possible to get back the large investment. Even if the elevator becomes successful, it will take several years before there are more elevators in the world to get in the competition for space traffic with the spacelines.

    Those who are looking for a little bit of adventure and have extra money to spend may want to consider a suborbital flight in space. While a suborbital flight may not be the space mission that you have always dreamed of, it will give you the rare opportunity to see what our planet looks like in a high - altitude flight outside our atmosl3here. So before you enjoy a trip by elevator to space, enjoy a suborbital flight first.

    Sharks(鲨鱼) are the most frightening animals in the sea. Sometimes we can see sharks swimming in the sea around Hong Kong. People put nets around some beaches to protect swimmers. When there is a "shark's flag", people must stay on the beach. It will be too late if a shark can swim sixty kilometres an hour to you.

    There are 30 kinds of sharks and 25 kinds of them are dangerous. The whale sharks are, very big. They can grow to 18 metres long, but they are not dangerous to people. The jaws(大白鲨) and the tiger sharks are the most dangerous kinds of sharks.

    Do you know all sharks must keep swimming, or they will go down?

All sharks can feel everything that happens around them. We must keep calm and don't make any noise when a shark is swimming near you.

    If a shark loses a tooth, a new one will grow out very quickly. So sharks always have many sharp teeth.

    Cars make our lives more convenient. But they can also be a problem. For example, fossil fuel(化石燃料) cars mainly cause air pollution.

    To improve the environment, many countries are developing electric vehicles(EVs，电动车). Among them, China is taking a leading role and has created the world's largest EV market.

    Last year, over 40 percent of the 753，000 EVs sold in the world were sold in China, more than twice as large as the number sold in the United States.

    "Filling up a fossil fuel car with gas(汽油) is more expensive than charging(充电) an electric car, " said Wu Hao, who bought an electric car this year.

    However, there are still some problems. It can be hard to find charging piles(充电桩) and the cars can't go far before needing to be recharged.

    Some of these problems are being solved. In 2014, China had 31，000 charging piles. Now China has the world's largest EV charging network, with more than 167，000 charging piles in total.

    Developing EVs is one of many efforts that China has made to cut down pressure on its environment after the government promised to stop increases in carbon dioxide emissions(二氧化碳排放量) by 2030.

    "As China goes, so will the world's car industry，" the Wall Street Journal said. China has taken a leading role in the world's electric vehicle industry.