A

    The most popular food in America was invented because a cook got angry. George Crum was a cook at a restaurant in Saratoga Springs, New York. One day in 1853, a customer(顾客) who had ordered fried(油炸的) potatoes sent them back to the kitchen. He wanted the cook to slice(切) them thinner and fry them longer. George Crum had a bad temper(脾气), and he thought the potatoes were fine the way he made them. To teach the customer a lesson, he sliced potatoes very thin and fried them until they were crispy(脆的). But instead of being angry, the customer loved the new fried potatoes. He asked for more. Other people who tried them like them too, and customers kept asking for them. Far many years, people called them Saratoga chips after the town where they were first made.

    Even now, after more than 150 years, potato chips are very popular. At least one of every ten potatoes grown in the United States is made into potato chips. So if you like potato chips, be glad George Crum had a bad temper!

Leonardo da Vinci was born on April 15, 1452 in Italy. He is best known as an artist today. One of his famous paintings is called Mona Lisa. However, Leonardo had many other natural abilities. He was also a great inventor. Many of his inventions have become important in modern daily life.

Although Leonardo hated war, he invented many different machines used for war. His most special invention was the machine gun, which was produced and used in war many years later.

    By watching the way birds fly, Leonardo tried to find out the secret of flying. Among his sketch (素描) we can see several objects. We consider them as modern flying machines.

    Leonardo spent many hours thinking about how to make good use of time. He developed ideas for labor-saving machines like cutting machines.

Leonardo was a strange man. He didn't eat any meat, which was very unusual in those times. He never published(发表) his ideas and scientific discoveries. He usually used mirror writing, which looks like writing in a mirror, starting from the right side of the page and moving to the left.

    We have very little of his work today. Leonardo finished only a few of his paintings. He left many unfinished because he thought they were not perfect. No one in his life time knew how great Leonardo was. We now believe, however, that he was one of the cleverest men the world has ever known.

    Before Monica goes to bed, she looks out of her window and sees the Moon. The Moon looks so beautiful. "I wish I could get the Moon," thinks Monica. But no matter (无论) how hard she tries, she cannot get the Moon. "Papa," Monica says to her father, "please get the Moon for me."

    Papa gets a very long ladder (梯子). He carries the very long ladder to a very high mountain. Then Papa puts the very long ladder on top (顶部) of it. Up and up he climbs. At last, Papa gets to the Moon.

    "My daughter Monica would like to play with you, but you are much too big," says Papa.

    "Every night I get a little smaller," says the Moon. "When I am just the right size, you can take me with you." After a few days, Papa takes it. Down and down he climbs.

    "Here," Papa says to Monica, "I have the Moon for you." Monica jumps and dances with the Moon. But the Moon keeps getting smaller and smaller. And at last, it disappears. Then, one night, Monica sees a small Moon come out. Each night the Moon grows, grows and grows.