David was a fifteen-year-old boy. He thought he was a young man, but his parents didn't think so. They told him, When you begin to think about helping others, you'll be a young man.”

    One afternoon, his parents gave David some money to buy some bread in a super- market. He saw an old woman there. The old woman looked very tired. David went up to her and found that the old woman lost her money and didn't have anything for her lunch. David took the old woman to go to the restaurant. But the old woman only ordered a glass of water for herself. David felt sorry for her, so he asked the waiter to bring the woman some bread and a cup of coffee. The old woman was so hungry(饿的） that she ate up all the food very soon. After that, she told David that she would never forget his kindness(慈善).

    David felt very happy. He thought he became(变成）a real young man.

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    On March 14, one of science's brightest stars went dark. Stephen Hawking, the world-famous British scientist, died at 78 in Cambridge, UK.

    Hawking is considered by many to be the greatest scientist in history since Albert Einstein. He came up with the theory（理论） that the universe (宇宙) began with the Big Bang and will end in black holes. His theories became the base for a lot of later research. He also wrote books to help common people understand the universe. His most famous book is A Brief History of Time, which has sold more than 10 million copies around the world.

    Besides his scientific achievements, Hawking was also someone who had a strong will. When he was 21, he got a serious illness that stopped him from walking and talking. Later in life, he had to sit in a wheelchair and “speak” using a computerized voice. But this didn't stop him from living a meaningful and colorful life.

    He celebrated his 60th birthday by going up in a hot-air balloon; when he was 65, he took part in a zero-gravity (零重力) flight to experience weightlessness. He hoped to travel into space one day. In 2015, Hawking spoke about how he felt life was unfair when he first knew about his illness. “But now, 50 years later, I can be quietly satisfied with my life,” he said.

    Tom goes to see his grandparents with his father. On the train, Tom often puts his head out of the window. His father says, "Tom, don't put your head out of the window. ''But Tom goes on putting his head out of the window.

    His father takes Tom's hat quietly, hides(藏)it behind his back and says to Tom, "You see, your hat is gone(消失)."Tom is afraid. His father says, "Well, whistle once. Maybe your hat will come back. "Tom whistles. His father puts the hat on Tom's head quickly. "Oh! It's wonderful! "Tom laughs and says. He quickly takes his father's hat and throws it out of the window. "Now it's your turn to whistle, Dad!" he says happily.

    One day, a man saw an old lady sitting inside her car at the side of the road. Though it was dark, he could see she needed help. So he stopped his car and walked towards her. The old lady was worried, even though she noticed the smile on his face. Was he going to hurt her? "I'll help you start your car, madam. By the way, my name is Bryan Anderson, " he said.

    While Anderson was fitting a spare tired (备胎) to her car, the lady began to talk to him. She thanked him much for coming to help.

    Anderson just smiled as he put his tools away. The lady asked how much she should pay him. He told her that if she really wanted to pay him back, the next time she saw someone who needed help, she could give them the help they needed. He waited until she started her car and drove off.

    A few miles down the road, the lady saw a small restaurant. She went in and a waitress came over with a sweet smile. The old lady noticed the waitress was nearly eight months pregnant (怀孕的), but she never let the pains and aches change her smile when she served her.

    The lady finished her meal and paid with a hundred-dollar bill. The waitress quickly went to get change, but the old lady was gone when the waitress came back. The waitress wondered where the lady could be. Then she found there was a note on the napkin (餐巾), "You don't need to give me anything back. Somebody once helped me out the way I'm helping you. If you really want to pay me back, here is what you do—do not let this chain (链子) of love end with you."

    Under the napkin were four more $100 bills.

    My friend's grandfather came to America from a farm in Thailand. After arriving in New York, he went into a cafeteria in Manhattan to get something to eat. He sat down at an empty table and waited for someone to take his order. Of course nobody did. Finally, a woman with a big plate full of food came up to him. She sat down opposite him and told him how a cafeteria worked.

    "Start out at that end," she said, "Just go along the line and choose what you want. At the other end they'll tell you how much you have to pay."

    "I soon learned that's how everything works in America," the grandfather told my friend later," Life's a cafeteria here. You can get anything you want as long as you want to pay the price. You can even get success but you'll never get it if you wait for someone to bring it to you. You have to get up and get it yourself."