One of the simplest inventions is the toilet. Before toilets, waste ran into rivers from people’s houses. Illnesses were common in big cities, and it was often difficult to find clean drinking water.

Animal food is another important invention. Before the invention, most animals were killed in the fall because there was not enough food for them in winter. After hay (干草) became a kind of common animal food, animals could live through the long winter.

The third great invention is glasses. Glasses help people read, write and do “close work” after the age of forty-five. Without glasses, the world would be difficult for the people above forty-five.

Take a trip up a hill on a windy day. What is flying high in the sky? It isn’t a bird or a plane. It is a kite!

Kids and adults like flying kites. Long ago, the first kites were made by Chinese people. Then, people around the world began flying kites.

One story tells a man’s hat got lifted off by wind. He had fun chasing (追赶) his hat, so he did it again! His hat became the first kite. Other stories tell that people liked watching leaves on windy days. They tied leaves to strings (线) and watched them fly.

Long ago, kites became important in keeping China protected. A man might be lifted up by a kite while he spied (监视) on an enemy.

He could use the kite to fly high like a plane. He could also fight from the air!

Kites come in many shapes, sizes, and styles. They are usually made of cloth or paper. A kite might be shaped like a bird, a fish, or just a box. Kites are also painted with colors.

You can use a kite to catch fish. First you tie a fishing line to a kite. Then you put bait (鱼饵) on the line. You watch the kite with hopes as it flies over the water. When you pull the kite down, you might find a fish on your line! Some people think this is more fun than using a fishing pole (杆).

Many countries have special days to honor kites. People make, sell and fly many types of kites.

There are several kite festivals in China. The Beijing International Kite Festival is usually held in April every year. People spend all days flying kites. You might see famous fighter kites. People fly these kites quite fast and try to cut other flyer’s lines.

There is much to learn about kites. From long ago in China until now, kites have had many uses. They have been used for spying, fighting, and fishing. But the best way to use a kite is to fly it high for fun.

“We don’t stop going to school when we graduate,” one group of Senior 1 students in Fuyang, Anhui, took these words quite seriously.

They have graduated from Fuyang Experimental Middle School. But the school still means a lot to them. They chose a special way to keep their memories of junior life alive — they recreated a digital version (数字版本) of their school in Minecraft, a video game.

In the game, they rebuilt every part of the school. They rebuilt the small garden, classroom buildings, sports field, their English corner and even the soccer field.

“Our 10-member team made a plan together, and then took our own parts to work toward our goal every day,” Wang Tian’ao, 16, the organizer said. They began with choosing photos of the real buildings. Then they drew sketches (草图) for the models. They also needed to measure (测量) buildings continually to make sure their creation was as accurate (精确的) as possible.

The hardest part was finding the most similar materials and colors. “For example, to recreate the huge glass wall of one of our classroom buildings has taken us a lot of effort. The glass wall is rich blue. But there wasn’t such a color in the game. So we had to use different colors to make the most matched color,” Wang said.

Although the project was not easy to them, their recreation was spoken highly of by people. “It’s just so much like the real school. It brings me back to the days in the school,” many graduates said.

Wang’s middle school teacher Wang Wei also said, “It’s amazing to see such a recreation full of creativity and hard work.”