When people eat, western people are used to using knives and forks. but Chinese people are used to using chopsticks. More than 3000 years ago, ▲ . Who invented the chopsticks?

Long ago, Chinese people used to eat with their hands. In Shang Dynasty, the last king, Zhou was cruel. He always killed people because the food was too hot or too cold. It made people afraid to serve him. His favorite Daji was also afraid.

One day Daji served King Zhou his meal. When she tried the dish for the king, she found that it was too hot. Daji felt very nervous because the king would be angry. Suddenly she had an idea and she used two pieces of her long hairpins (发簪) to put the food to the king’s mouth.

The King Zhou found it so interesting to eat with two long sticks that he forgot how hot the food was. After that, Daji thought it was a good way to solve this problem and asked people to make two long-thin gold sticks. People found it better to eat with sticks than with their hands. But they were too poor to afford the gold sticks. Then they found bamboo was good material to make chopsticks. Since then, people have invented chopsticks.

Many years ago, while three-year-old Louis Braille was playing with an awl in his father's workshop in France, he accidentally hurt one of his eyes. He immediately lost sight in that eye. Soon, germs（细菌）got into his wounded eye and spread to his other eye. In a couple of years, Louis went completely blind.

When he was ten, he attended a school for blind boys in Paris. One day, a soldier came to visit. The soldier knew a special code that was used in war. It was called "night writing", which had twelve raised dots. Using these special dots, soldiers could pass secret coded messages without speaking. They ran their fingers over the dots and found out the meaning of the words even in total darkness.

Young Louis realized that this could be a way for blind kids to read. Later, he reduced the number of dots from twelve to six and made many other improvements. Still, his special code was not accepted by others. But Louis didn't give up and he worked on it all his life.

After his death, his dot reading code caught on. It was soon being used everywhere to teach blind children to read. They could now use their hands to feel the dots, which gave them a new freedom to read. Today, this reading code is named after young Louis. It's known as Braille.

People began to make robots about several（几个）hundred years ago. In the past, some of the early ones looked like animals or humans. However, they could not talk and were pretty dumb. They worked like clocks and did the same things over and over again.

Now modern robots do not always look like people. Some are like big machines; others are nothing but long arms with boxy（箱子般地）bodies. However, modern robots are smart. Some can work out（解决） problems on their own. Their brains（大脑）are computers and their eyes are sensors（传感器）. Motors（发动机）help them move.

In the future, robots will learn from their mistakes more than they do now. They will be smarter. It is possible that we will have robot judges（评判员，法官）, robot house workers, and robot factory workers. Robots will help people to do more things.