Mr Jones, the owner of a farm, was one day driven out of the farm by all the animals he kept．The animals were excited to be masters of their farm．Animals made seven rules of their own and Snowball painted them on the wall．

    ⒈Whatever walks on two legs is an enemy;

    ⒉Whatever walks on four legs, or has wings, is a friend;

    ⒊No animal shall wear clothes;

    ⒋No animal shall sleep in bed;

    ⒌No animal shall drink alcohol(酒);

    ⒍No animal shall kill any other animal;

    ⒎All animals are equal．

    They were nicely written, except that "friend" was written "friend"．Snowball read them out, and all the animals agreed．

    "Now, let's go to the field．Let's get in the harvest more quickly than Jones and his men could do．"

    But at this moment the three cows, who had seemed uneasy for some time, shouted because they hadn't been milked for 24 hours．Then the pigs began to help milk the cows successfully．Soon there were five buckets (桶) of creamy milk at which many animals

    looked with great interest．"What's going to happen to all the milk?" asked one animal．"Jones used to mix some of it in our food," said one of the hens．"Never mind the milk," cried Napoleon, standing in front of the buckets, "the harvest is more important．Mr Snowball will lead the way, and I'll follow in a few minutes．"

    So the animals ran down to the field to begin the harvest, and when they came back in the evening, it was noticed that the milk had disappeared．

    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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    Today, after 10 days of medical treatment, for the first time, I went out alone to meet a motherly lady who I had met during my stay in a program. She had been unwell recently and I lived alone. Her sons live in foreign countries.

    After I called her and told about my plan to visit her, she started becoming excited and happily planning food at once. Nowadays, she has a lady cook coming by to help her but she does part of the work herself with her bandaged leg.

    I reached her home alone after being guided a couple of times by her before. I carried little things (snacks, books etc.) for her. She had been waiting for some time when I arrived. We talked about different things from health to her life and mine, from past to future, from food to travel etc. During the discussion, her care for me became clear when she made warm suggestions or supported me.

    During the last few months, she had struggled with health and housework. She had got over those difficulties and here she was telling me how all of us must face some problems. She had seen a few people facing worse problems in the hospital and mentioned about their cases and was grateful for her present condition which was manageable.

    She wanted to gift me something—she kept thinking of a dress, watch, footwear etc. whatever was new and great in her home. I kept refusing but finally took the footwear out of politeness.

    She loved the snacks I had brought and wanted to eat them with her tea. I was quite happy to see the child like interest.

    While I was spending time with my motherly friend, the following thought kept coming back to me-probably this is why I have lived through the 10 days in this city. The time I spent with her seemed so much needed. I felt the deep peace it could bring to me and that brought such a big joy!

    The famous scientist and thinker, Charles Darwin, was born on February 12, 1809.As a boy, Charles liked to go for walks in the fields and forests. He enjoyed watching nature, and comparing what he saw with everything he had read in science books. He also liked collecting very much. He collected many things, such as birds, eggs, stones and leaves.

    At sixteen Darwin was sent to the University of Edinburgh to become a doctor. But he was interested in the history of nature.

    Then he was sent to study in the University of Cambridge. There he studied until 1831.

    Some time later he heard that the ship Beagle was going on a trip to South America and wanted a scientist. His teacher advised him to go. So when the Beagle left England in December, 1831, Darwin was on it.

    The trip lasted almost five years. Darwin saw many new plants and animals. He collected all kinds of plants.

    In 1842 Darwin went to live in Kent, and there he continued his studies of change in nature. Darwin understood that plants and animals are not always the same, and that they really change.

    By 1859 Darwin had finished his famous book The Origin of Species. It made a great hit in the world of science. He was opposed(反对)by the church and even by some scientists. But later, more and more scientists agreed with him.

    In1871 Darwin wrote another important book. Darwin continued his studies in science until he died in 1882.

    Mr. and Mrs. Scott want to buy some new chairs for their new house. They come into a shop and see some very good chairs on the floor. They like the colour and want to know how much they are. They see a price tag (标签) on one chair. It says (上面写着) "￥100". They like the chair but they are too dear (贵) for them. The Scotts don't think they can buy them now. They leave this shop and go to other shops. Mr. Scott thinks they can find some cheap chairs.