I was in a shopping mall, so I decided to go and get a cup of coffee. As I was making my way to the coffee shop, I noticed an old gentleman poorly dressed sitting near the shop. I knew from the first sight that he needed help. He had a little lunch in front of him and was enjoying it. It was clear that he had a problem with his right eye. I then joined the line and waited to be served.

    Then it happened. One of the most beautiful gestures(姿态) I had ever seen in my life. There was a young man in front of me in the line who was also waiting to be served. The next thing I knew was that the young man handed the waitress(女服务员) 20 dollars and requested a glass of juice as a favor(善行). The waitress looked at the young man a little perplexed, not fully understanding the request. That was when the young man asked her to give the juice to the old gentleman eating his lunch outside, as well as the change(零钱) from the 20 dollars. The young man also told her that he would be watching every second so that she would be completely safe.

    Then there was a wonderful exchange between the waitress and the old man. I only wished I could take a photo of the smiles on both of their faces.

    As I was considering this event later, I wondered why the young man didn't perform this act of kindness himself. Maybe he was hoping that this act of kindness might inspire(激励) others to do something for this old man as well.

      More and more people think it necessary to study in an English-speaking country and it didn't take long at all for me to decide to come and study in UK.

      I have been used to school life since I came here two months ago, and I am starting to enjoy most of my time in here. School starts at 9 o'clock every morning, and every Monday, Wednesday and Friday we have long days, in which we have 9 lessons and school finishes at 4 o'clock. Every Tuesday, Thursday and Saturday we have short days, in which we have only 6 lessons and finish at 1 o'clock. After lessons, we have  hours of activity time, when you can choose from a number of activities, including many sports, such as rugby(英式橄榄球) , football, basketball and tennis.

As a boarder(寄宿者), the quality of food is something I consider very important, and Merchiston has not let me down. The school kitchens are run by a professional company, and the quality of food is excellent, and they are always trying to make the diet healthy. One of the obvious advantages of being a boarder is that we can have breakfast in the school, which means we don't have to pull ourselves out of bed as early as the day pupils!

    What was discovered by accident? The answer is penicillin (青霉素). It kills germs. By killing germs, it saves lives. Suppose you are sick. You go to a doctor. She examines you. She says you have a “staph” infection (葡萄球菌感染). She gives you some medicine. You take it. The medicine knocks out the staph. Soon you are well. Before penicillin, this would not happen. Staph was almost sure death.

    Everyone wanted a medicine. Laboratories worked day and night. They grew the staph in small dishes. Then they tried to kill it. Nothing worked.

    The laboratory dishes had covers on them. They kept things from falling into dishes. Molds (霉菌) were a big worry. They are always in the air. You can't see them. They're too small. There are thousands of different molds. Molds can make an experiment (实验) fail. That's why dishes are covered.

    Dr. Alexander Fleming was working to kill the staph germ. He worked for years. One day he took a cover off a dish. He looked inside. There was a thick growth of staph germ. There was also some mold. Then he saw something strange. Where the mold was, there was no growth of staph. This is what Fleming probably thought. “By accident, I found a mold to kill the dreaded staph.”

    This is how penicillin was found. But here's the real miracle (奇迹). There are thousands of kinds of molds. But only one kind can kill staph. The mold must have fallen into the dish a few days before. The cover was probably off only a few seconds (秒). In those few seconds the right mold fell into the right dish. Another man might have thrown the dish away. But Fleming was very careful and smart. He understood what the mold did. How lucky the humans were!

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    One day a king went to a faraway place in his country. When he came back, his feet hurt a lot. "There are too many small stones on the roads. They hurt my feet. You should cover every road with leather(皮革)," he told his men. Of course, it would cost a lot of money. One of his men was very smart. He told the king, "Why not cut a little piece of leather to cover your feet?" The king was surprised, and he agreed to the man's idea. He asked his men to make a pair of leather shoes for him.

    Maybe this is not the beginning of leather shoes. But it teaches us a lesson of life: if you want to make this world a happy place to live in, the best way is to change yourself, not the world.