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    Driverless(无人驾驶的)technology is quickly progressing with many cars being tested on roads around the world．Now, researchers in Singapore are testing a self-driving scooter，which has four wheels and a seat．It can move at a speed of up to six kilometers an hour．Researchers said the scooter was built with materials that did not cost much money．

    The scooter was developed by the National University of Singapore．Researchers at the Massachusetts Institute of Technology(MIT)also took part in the project．It was designed(设计)for people who cannot，should not or do not want to drive a car．It could help older adults，the disabled or people who are too young to drive．

Marcelo Ang，a researcher at the National University of Singapore，says the scooter can be especially useful for people who use wireless devices(无线设备)while walking on city streets，because there is a sensors(探测器)in it． “I'm sure you have experienced people who almost run into you while using their phones on the street．Would it be so nice to drive the scooter without worrying about the safety?”he says．Besides，developers of the scooter say it can work together with ride—sharing services to make trips completely easy and safe．

The researchers hope the scooter will reduce the need for cars，which can lower pollution and reduce accidents．

    Marcelo Ang says the scooter has completed many successful tests at the university．Kevin Xiangyu Hui，a university student．tested the scooter and said he found the ride was very smooth and safe．“When I sat on this machine．I felt really relaxed and it was really cool．”The scooter has yet to complete lots of road tests so it is not available to buy at present．

A

    What picture do you have of the future? Will life in the future be better, worse or the same as now? What do you hope for about the future? Scientists think that life will probably be very different in 2050.

    First of all, it seems that people won't use TV channels by 2050. Instead, people will choose a program from a "menu" and a computer will send the program directly to the television.

    Water will become a very serious problem. We'll need much more water, but there won't be enough. Some scientists think that water would be the cause of war.

    Cars will run on new clean energy and they will go very fast. And there won't be any accidents with the help of computers. On the other hand, space planes will take people around the world in two hours.

   Robots will work in factories instead of people. Many factories have already used robots. Big companies prefer robots—they do not ask for money, and they work for 24 hours a day.

    In a word, by 2050, our life will change a lot and our future will be quite different from now.

    In many high schools, there are strict rules about using mobile phones. If your phone rings in class, for example, the teacher will be very angry.

    Every mobile phone has a ringtone (铃声). It tells you that someone is calling you. Now, there is a ringtone called “mosquitotone (蚊子铃声)”.

    Mosquitotone has a special sound. Only children and teenagers can hear it. As we get older, we are unable to hear some sounds with high frequencies (频率). As a result, a child or teenager can hear the mosquitotone ringtone, but someone of 20 or older can't.

    But sometimes, people over 20 can hear the ringtone. One British student's phone uses mosquitotone. In class, the student's phone rang. The 22-year-old teacher looked at the student and became unhappy. “I heard that. You know the rule：no mobile phone in class. ”

    Not all the students are interested in mosquitotone. Jerry Jones, a high school student of 17, says, “Using mosquitotone too often is bad for our hearing. I may use it for pleasure, but not in class. It's unfair(不公平的) to the teachers！”

    What do parents think of mosquitotone？“I think it is perfect for places like movie theaters,” says Connie Neeson, 44. “Think about it. You're watching a film and someone's mobile phone rings. Mosquitotone is good because many people don't hear it. However, it also has a bad influence（影响） on their study if students use it in class. ”

    Computers can injure you. Most other injuries happen suddenly. For example, if you fall off a bicycle and break your arm, it happens very quickly. But computer injuries happen slowly.

Your eyes

    Too much light can injure your eyes, so never sit too close to a computer screen. Your eyes should be at least 50 centimeters from the screen. Remember to look away from it sometimes. This gives your eyes a rest.

    When you use a computer, the window should be on your left or your right. If it is behind you, the light will reflect(反射) on the screen. If the windows is in front of you, the sun and the screen will both shine into your eyes.

Your hands and wrists(手腕)

    Hand and wrist injuries can happen because the hands and wrists are moved in the same way hundreds of times. If you use a keyboard for a long times, follow these three rules:  1) Rest your wrists on something.  2) Keep your elbows at the same height as the keyboard.  3) Stop sometimes and exercise your hands, wrists and fingers in a different way.

Your back

    Some people sit for many hours in front of a computer. If you sit in a wrong way, you can injure your back or your neck. So you should sit with your back straight. The top part of the screen should be in front of your eyes. Your forearms(前臂), wrists and hands should all be parallel to(与......平衡) the floor. If you are sitting for a long time, get up every 30 minutes and exercise your arms, legs and neck.

    Enjoy your computer, but use it safely.

    Tablets are really useful devices, but their big screens always make them as a burden to carry around without a bag. Wouldn't it be great if there were a phone with the powers of a tablet that could be folded up and fit into the hand?

Now something like a tablet-shaped but foldable phone is about to become available. In February, South Korean electronics company Samsung and China's Huawei both showed foldable phones, The Galaxy Fold and Huawei Mate X respectively. Mobile phone use has entered the "foldable future", The Verge noted.

    The technology could change our lives in unusual ways. These devices, due to their foldable screens, give us the larger screens we want. At the same time, they still fit easily into the pocket. As USA Today noted, they're "the combination of a small tablet and smartphone, all in a single device".

    The technology could change other devices too. For example, we could make TVs that stick to walls like posters, or fold up easily to hide away in drawers. In crowded modern cities, they will help us to make full use of available space.

    In a keynote speech, Samsung's senior vice president of mobile product marketing, Justin Denison, called the foldable screen "the foundation for the smartphone of tomorrow". "It's a piece of white paper for us to paint something beautiful on together," he said.

    So is there nothing to stand in the way of the foldable future?

According to technology news website Android Authority, the necessary displays* were difficult to produce. At present, these foldable devices cost too much. For example, the price of Huawei Mate X is 17,500 RMB. That's a price that few people will be able to afford.

    But if the foldable device isn't going to change the world overnight, there is no doubt that it is coming.

    Patrick Moorhead, an industry expert told The Verge, "Few are debating if foldable mobile displays are the future of smartphones; the only question is when and by whom."

    More than 1,000 different kinds of pieces of plastic, including 115 cups, 25 bags, four bottles and two pairs of shoes, have been found inside a dead whale(鲸鱼) in Indonesia, according to local officials.

    When the whale was found on the island, it was already decomposing when animal doctors arrived. So they were unable to be sure if the plastic caused its death, said Lukas, the leader of the World Wildlife Fund in Indonesia. The plastic weighed about 6 kilograms, or 13 pounds, he said.

    But pictures of the dead whale caused a warm discussion. The people in the country have started to realize that it is because of using too much plastic. So has the government. Indonesia, a nation of about 260 million people was the world's second-biggest producer of plastic waste in 2018, behind only China.

    If the whales eat too much plastic, they will have a wrong feeling. They think that they are full. And that will lead them to eat less food that provides all the good things they need, said Nicholas who is the leader of the Ocean Conservancy. Moreover, eating too much plastic can make them reduce their weight, their energy and slow down their swimming. As a result, whales are easier to be hurt by the sharks and many other dangerous animals in the sea.

    More than 800 kinds of animals in the sea are affected by about 8.8 million tons of plastic which is thrown away freely in the ocean each year. Plastic can also stop the animals moving freely and sometimes they will cause them to die because they have to be under the water for too long. Some plastic can make a small hole in their stomachs after they eat it.