I was 8 years old when I found out my father was ill. It was 1993, but I can remember my mother's words as if it were yesterday. “Jessica, I don't want you to take food from your father, because he has AIDS. Be very careful when you are around him.”

    AIDS wasn't something we talked about in my country when I was growing up. From then on, I knew that this would be a family secret. My parents were not together anymore, and my dad lived alone. For a while, he could take care of himself. But when I was 11, his condition worsened. My father's other children lived far away, so it fell to me to look after him.

    We couldn't afford all the necessary medication for him, and because Dad was unable to work. I had no money for school supplies and often couldn't even buy food for dinner. I would sit in class feeling completely lost, the teacher's words muffled as I was thinking how I was going to manage.

    I didn't share my burden (负担) with anyone. I had seen how people reacted to AIDS. Kids laughed at classmates who had parents with the disease. And even adults could be cruel. When my father was moved to the hospital, the nurses would leave his food on the bedside even though he was too weak to feed himself.

    I had known that he was going to die. But after so many years of keeping his condition a secret, I was completely unprepared when he reached his final days. Sad and hopeless, I called a woman at the nonprofit (非营利的) National AIDS Support. That day, she kept me on the phone for hours. I was so lucky to find someone who cared. She saved my life.

    I was 14 when my father died. He took his secret away with him, having never spoken about AIDS to anyone, even me. He didn't want to call attention to AIDS. I do.

    Once there is a boy in London. His name is Jimmy. He starts painting when he is three years old, and when he is five years old, he is already very good at it. He paints many beautiful and interesting pictures, and a lot of people buy his pictures. They say, “This boy is going to be famous when he's a little older, and then we're going to sell these pictures for a lot of money.”

    Jimmy's pictures are different from others' because he never paints on the whole of the paper. He only paints on half of it, and the other half is always empty.

    “That's very clever,” people say. “No other painters have ever done that!”

    One day someone asks Jimmy, “Please tell me, Jimmy, why do you only paint on the bottom (底) half of the paper, but not on the top half?”

    “Because I'm small,” Jimmy says, “and my brushes can't reach very high.”

    It's Sunday. There are many people in the bus. And an old man is looking here and there. He wants to find an empty sea（t  座位）. Then he finds one. He goes to it. A small bag is on the seat. And a young man is sitting beside it.

    "Is this seat empty（空的）?" asks the old man.

    "No, it's for a woman. She goes to buy some bananas." says the young man.

    "Well," says the old man, "Let me sit here please. When she comes back, I will leave here." The bus starts（启动）.

    "She doesn't come, but her bag is here. Let me give her the bag." Then the old man throws the bag out of the bus window.

    The young man jumps up and shouts, "Don't throw（扔）! It's my bag!"

    Life is full of surprises and you never know how things will turn out.

    Sir John Gurdon is a good example of this. As a boy, he was told he was hopeless at science and was at bottom of his class. Now, aged 79, the very same Gurdon shared the 2012 Nobel Prize in Medicine with Japanese stem cell (干细胞) researcher Shinya Yamanaka.

    Like so many scientists, Gurdon shows us where the power of curiosity and perseverance(坚持) can lead.

    When he was 15 in 1948, Gurdon ranked last out of the 250 boys at his high school in biology and every other science subject. Gurdon's high school science teacher even said that his dream of becoming a scientist was "quite ridiculous".

    In spite of his teacher's criticisms(批评), Gurdon followed his curiosity and kept working hard. He went to the lab early and left later than anyone else. He experienced thousands of failures.

    "My own belief is that we will, in the end, understand everything about how cells actually work," Gurdon said.

    In 1962, Gurdon took a cell from an adult frog and moved its genetic (基因的) information into an egg cell. The egg cell then grew into a clone of the adult frog. This technique later helped to create the sheep Dolly in 1996，the first cloned mammal(哺乳动物) in the world.

    In 2006, Gurdon's work was developed by Yamanaka to show that a sample(样本) of a person's skin can be used to create stem cells. Using this technique, doctors can repair a patient's heart after a heart attack.

    "Luck favors the prepared mind," Gurdon told the Nobel Prize Organization. "Ninety percent of the time things don't work, but when they do, you have to seize(抓住) the chance."