Mike wants to fly like a bird. His father tells him, "You can't fly like a bird because you are too big." "Why can't I? Some birds are big, but they can fly!" The boy doesn't understand. Bill is crippled. He wants to walk and run like other kids. "Why can't I walk or run like other kids?" Bill thinks.

      One day, the two boys meet in a park. "Do you want to fly like a bird?" Mike asks Bill. "No," Bill says. "I only want to walk and run like you."

      Then Mike walks to Bill's father. He says something to him. "That's OK," says the father. Mike goes to Bill and says, "Get on to my back．Let's run." Then Mike runs with Bill on his back. Bill is very happy and says, "We can fly, Mike! We can fly!"

    A baby giraffe is born 10 feet high and usually lands on its back. Bringing a giraffe into the world is a tall order. In his book, A View from the Zoo, Gary Richmond describes how a new-born giraffe learns its first lesson.

    The mother giraffe lowers her head long enough to take a quick look. Then she puts herself directly over her child. She waits for about a minute, and then she does the most unreasonable thing. She throws her long leg and kicks her baby, so that it's sent sprawling (四脚朝天).

    When it doesn't get up, what the mother has done is repeated again and again. The struggle (挣扎) to rise is important. As the baby giraffe grows tired, the mother kicks it again. Finally, it stands for the first time. Then the mother giraffe kicks it off again. Why? She wants it to remember how it can get up. In the wild, a baby giraffe must be able to get up as quickly as possible to stay with its group, where there's safety.

    Another writer named Irving Stone understood this. He spent a lifetime studying great people, writing stories about such men as Michelangelo, Vincent van Gogh, Sigmund Freud, and Charles Darwin.

    Stone was once asked if he had found something unusual about these great people. He said, “I write about people who sometime in their life have a dream of something. They're beaten over the head, knocked down and for years they get nowhere. But every time they stand up again. And at the end of their lives they've realized some small parts of what they set out (着手) to do.”

    One pleasant evening, I was holding Grandpa's hand and taking a walk in the park. "Where are the peanuts? Give me now!" He suddenly said. How I wished I had some with me! "William, the monkeys are taking long to come out today. Wait till they smell the peanuts." I knew he was lost in one of his memories again. I remembered the stories he told me of how he fed the monkeys when he was a kid. Then, he saw the goldfish! He acted as if he was seeing them for the first time.

    Poor Grandpa! He fell ill with Alzheimer's disease (阿尔茨海默症) last year. The doctor said it was a progressive brain disorder which could destroy (破坏) a person's memory. The patient might also not be able to make reasonable judgments (判断). The saddening part was that it was a lifelong disease. But when my parents invited him to stay with us, he refused and said he liked living alone. One day, he forgot to turn off the fire after cooking porridge. Luckily, one of the neighbors came to help him before the fire could spread.

    It was then that my parents brought Grandpa to live with us. Often, he would forget my name and ask me who I was and what I was doing in his house. Each time I would answer softly, "It's me, Ray, Grandpa!" Even if he had forgotten who I was, he would always be my beloved grandfather.

Do you know how to learn a new language quickly? The best way is to put yourself in the language.

Talk with a native speaker(讲母语的人).People often spend too much time learning grammar. However, speaking with a native speaker can help people learn better. If a friend around you can speak the language you plan to learn, try to ask him or her for help. If it's hard to find such a person in your real life, you can make a pen friend online. Of course, you can travel to a country where the language is spoken. It doesn't matter whether you speak the language well or not. When you communicate in it, you are improving your speaking.

Use the language as much as you can. People often say they have learnt a language for many years, but their speaking is still not fluent (流 畅 的). In fact, they perhaps speak the language for only a few hours a week in these years. If you want to learn a new language quickly, remember to use it every day. If you can save your break time, you can learn extra (额外的) 20 or 30 words a day.

28th July, 1973, is a big day for fish. Two little mummichogs(花鳉) became the first fish in space. They lived in a plastic bag aboard Skylab. Three weeks later, they learned how to swim in zero gravity(零重力).

51 years later, four zebrafish are now swimming aboard China's Tiangong Space Station. This is for a space experiment to see how very little gravity changes how fish live and grow.

 We know people feel weightless in space. But very little gravity can cause more changes. It affects almost all our body activities. If we' re going to live more in space in the future, we need to understand these changes. People are hard to study though. So, scientists study fish instead.

 Zebrafish have helped us learn about living things. They may seem different, but have many similar body parts with us. "Their bodies often work like ours," explains Aaron van Loon, a biologist at the University of Washington.

 Zebrafish are also small and easy to take care of. And, they' re clear before they are born. Scientists can look inside them while they' re growing.

 Zebrafish have been in many medical studies. In space too, they' re studied since the 1970s. In 2015, zebrafish on the International Space Station helped learn how muscles get weak in very little gravity.

 Like astronauts, fish are carefully picked for space trips. They always have a job to do. Our little friends in water are helping us learn to travel in space safely.