A Cloud of Hope and Danger

    In 2050, a small cloud floats through the air in a hospital operating room(手术室). In the room a patient, suffering from cancer, lies on a table. The cloud surrounds (包围) the patient, her body and filling her lungs (肺). The cloud is not smoke or steam. It is made of millions of microscopic robots called nano-robots(纳米机器人). These tiny robots move from cell(细胞) to cell in the body, destroying the cancer cells.

    Fighting cancer with nano-robots is only an idea today, scientists say that it would be possible in the future. Using nano-robots for good purposes such as fighting disease or repairing the environment may be the to many of today's problems.

    However, nano-robots could be a risk as well. Since nano-robots are so tiny, they will have to work in large teams of many thousands to 'many millions. For this reason, nano robots will have to be programmed to build . Scientists will not have the ability to build millions of nano-robots one by one.

    This to reproduce(复制)is making some scientists worried. What if something goes wrong in the programming? Quite a lot of crazy nan-orobots would be far than any disease. Some people think that if they get out of control, nan-orobots could destroy the Earth.

    What should be done? Should we continuenan-orobots or should we search for other methods? This is one of the many difficult that we have to make in the future.

Today, we still have some environmental problems. As a middle school student, we should do something to improve more environmental .

On the one hand, we ourselvesdestroy the environment, such as throwing the rubbish about. We canpart in some commonweal（公益）activities to plant more trees, for the trees are good to our environment. On the other hand, if someone does harm to the environment, like spitting on the ground or stepping on the grass, we can stop them from so, If there's a factory which destroys the environment, we can tell the relative（相关）department or the police about it.

All in all,  we are students, we can still do a lot to protect our environment, and we should take action from now on.

When Ariel rode her bike to the riverside, last November, she planned to go hiking and bird-watching. Bingo! A mile into her walk, she a beautiful swan(天鹅) lying near the riverside. Ariel had worked at the Wild Bird Fund rehab center (康复中心) and knew that swans can be aggressive(攻击性的). But as she got close to this one, she found that it was hurt. "I it, or it will die," she thought.

Ariel put her jacket over the bird's head it calm. She gently picked it up, and held it in her arms. And then she thought, "What do I do now?" Her best choice the rehab center, but that was across the river and on the other side of the city. How was she going to transport a 17-pound swan on her bike all that way? Luckily, when she around for help, some strangers drove by and offered her, her bike and the swan a ride to a nearby subway station.

Ariel called the rehab center on the way, and an animal-care manager picked her up at the subway station and drove the bird, the bike and her to the center. There, the swan , treated and taken good care of. By now, the bird many swan friends there, and it is living a happy life. It's really a happy ending.

 The real story is just how far some people are willing to go to save a swan in the big city. In all, Ariel spent two hours on foot, by car and subway. "If an animal is in danger, I whatever I can. I always happy because of this," she said.

That's the perfect summary of who she is. Do you agree?

A Cloud of Hope and Danger

    In 2050, a small cloud floats through the air in a hospital operating room(手术室). In the room a patient, suffering from cancer, lies on a table. The cloud surrounds (包围) the patient, her body and filling her lungs (肺). The cloud is not smoke or steam. It is made of millions of microscopic robots called nano-robots(纳米机器人). These tiny robots move from cell(细胞) to cell in the body, destroying the cancer cells.

    Fighting cancer with nano-robots is only an idea today, scientists say that it would be possible in the future. Using nano-robots for good purposes such as fighting disease or repairing the environment may be the to many of today's problems.

    However, nano-robots could be a risk as well. Since nano-robots are so tiny, they will have to work in large teams of many thousands to 'many millions. For this reason, nano robots will have to be programmed to build . Scientists will not have the ability to build millions of nano-robots one by one.

    This to reproduce(复制)is making some scientists worried. What if something goes wrong in the programming? Quite a lot of crazy nan-orobots would be far than any disease. Some people think that if they get out of control, nan-orobots could destroy the Earth.

    What should be done? Should we continuenan-orobots or should we search for other methods? This is one of the many difficult that we have to make in the future.

When the other models appeared on the stage, the audience cheered and clapped. Then it was Niu's turn. The audience suddenly became . However, after four or five seconds, Niu heard someone next to the stage say in admiration, "So cool!"

Niu Yu, 24, became a(n) star at Shanghai Fashion Week for her confidence, even though she was wearing a prosthetic leg. When Niu was only 11, she lost her right leg during the Wenchuan Earthquake.

Niu has won lots of praise. This gives those who have prejudice(偏见)against the disabled a hit on the nose. "I by something they said. They said the traditional view was that sports were for people with legs, but sports should be a kind of spirit. Even though I have lost a leg, I still deeply love sports and will do so forever, " Niu said. Actually, Niu first drew the public's attention when she a marathon — a 42-kilometer race in 2018, which was held in Wenchuan to mark the anniversary （周年纪念）of the earthquake.

Now, Niu works as a photographer and has more than 850,000 on social platforms, such as Douyin. "I feel I have a social responsibility to bridge the disabled and the public. Showing my life to the public can allow them to understand our group and can also tell other disabled people that our society is more tolerant（宽容）than they imagined, " she explained.

Laughter is good for you, and that's no joke! A good laugh helps you right away. When you laugh, changes in your body. For example, you take in  air than usual, which is good for your heart. A good laugh increases your heart rate. When you laugh, your brain also releases (释放) chemicals that make you feel happy. Laughing can also make you feel relaxed for up to 45 minutes.

Laughter can  reduce pain. You probably don't want to chuckle (偷笑) when you're hurt, but laughter helps the body make its own  medicine. Laughing is also great exercise! Research  that laughing 100 times is as good as riding a bike for 15 minutes.

So why don't you try laughing out loud every day?