Have you ever walked along the Silk Road? Do you know the famous Silk Road? The Silk Road was an ancient network of trade routes（贸易路线）connecting the East and the West. 

People used to do business with others from different countries along these routes. Scientists and archaeologists（考古学家）believe people began to travel along the Silk Road centuries ago. By the time the Chinese silk trade became important in the world, the Silk Road had covered almost 6,500 kilometers. It started from China and finally got to Rome. 

Merchants（商人）traveling along the Silk Road carried silk, of course. They also carried and traded in tea, cloth, gold, jewels and other things. During its busiest time, the Silk Road attracted（吸引）people from many different countries, such as China, Iraq, Turkey and Greece. All those people traveled along the Silk Road to share goods, stories, ideas, languages and cultures. 

In modern times, the old Silk Road is still useful, but now people use trains instead of camels and horses to travel. They have realized the Silk Road is becoming more and more important among countries. So they, especially Chinese people, are trying to make better use of it. There is even a Silk Route Museum in Jiuquan, Gansu Province. It has over 35,000 objects about the Silk Road. In this way, China protects the history of many countries. 

Museums are some of the best places to go out in London. You can visit them for a day. Most of them are free. One day I went on a trip to the science museum with my dad. I really liked the place. 

First we had a look at a new free show called Dan Dare and the Birth of High-tech Britain. It explained an important time in British history. From it we knew that British technology improved after the war. It was about the story of Dan Dare, a classic British science fiction comic hero. He was the leader of all the pilots on a spaceship. 

After that, we went to the Energy Gallery (能源长廊), the museum's latest interactive (互动的) gallery. When we saw it, we realized we need and use energy not only at present but also in the future. There were over 50 interactive shows. They taught us about the world of physics. The workers were excitedly explaining the shows while we watched them. 

Finally, we went to the Antenna Gallery and got the latest science news. But I couldn't study all the galleries in one day. There were just too many to see! What a pity!

In Britain, Boxing Day is usually celebrated on December 26th, which is the following day after Christmas Day. However, strictly speaking, Boxing Day is the first weekday after Christmas. Like Christmas Day, Boxing Day is a public holiday. This means it's a non-working day in the whole of Britain. When Boxing Day falls on a Saturday or Sunday, the following Monday is the public holiday.

The exact origin (起源) of the holiday is unclear. One of the thoughts is that during the Middle Ages, when great sailing ships were setting off to discover new land, a Christmas Box was placed by a priest (神父) on each ship. Those sailors who wanted to ensure a safe return would drop money into the box. It was sealed up and kept on board until the ship came home safely. Then the box was handed over to the priest in the exchange for the saying of a mass of thanks for the success of the sailing. The priest wouldn't open it to share the contents with the poor until Christmas.

One more thought is about the "Alms Box" placed in every church on Christmas Day. Worshippers (做礼拜的人) put gifts for the poor into it. These boxes were always opened the day after Christmas, and that is why that day became known as Boxing Day.

Today, many businesses, organizations and families try to keep the traditional spirit of Boxing Day alive by donating (捐赠) their time services and money to aid Food Banks, providing gifts for the poor, or helping families in need. Besides, spending time with family and shopping are popular Boxing Day activities now.

When did the first man appear? Although early humans didn't leave any written records, they left many paintings on the walls of the caves (洞穴) where they lived. From these paintings, we know that early humans walked on four limbs. Also, they did not live at one place but moved from place to place in search of food and water.

Without any tools, early humans used stones and wood to dig and cut their food. They also used these to protect themselves from animals. Because stones were used to make tools, this age was called Stone Age.

With time going, tools made of stones and wood were replaced (代替) with metal ones. Metals(金属) were also used for farming and making knives.

The first fire that early humans noticed was natural fire caused by lightning. With fire, early humans could now light up dark caves. They could keep themselves warm during cold weather and cook meat. Also the fire could drive animals away.

Early humans noticed new trees growing from the seeds (种子) that fell to the ground from the fruits. This gave them the idea that they could make their own food by planting seeds, which led to farming. With the beginning of farming, early humans began to live in one place. They moved out of the caves and lived on farms and near the fields together, then the first villages appeared.

Raising animals changed the life of early humans. The wild dogs were probably the first animal to be raised. As time went, goats, sheep, cows, and horses were kept, too. This led to herding (畜牧业).

The paper money in your wallet has some new friends. China has upgraded the fifth edition (版本) of the renminbi (RMB) . The new money has brighter colors and new security features (防伪特征) . 

In fact, China was the first country to use paper money.  It was used during the Northern Song Dynasty (960-1279) . 

For about 1,000 years, paper money has played a big part in our lives. But things have changed in recent years.  More people are paying for things with the WeChat Wallet and Alipay mobile apps. 

Does this mean paper money will go away one day? Maybe. But not for now, according to The New York Times. 

 First of all, not every country is going cashless (不用现金的) . Paper money is still widely used in most countries. There is also the danger of hacking (黑客攻击) . If you pay for everything online, someone could hack into your phone and take your money. 

So, you may still want to keep some paper money on hand, just in case. 

On the road toward a cashless future, one country is farther ahead than others—Sweden. Sweden plans to become the world's first cashless country by March 2023. People will mostly use bankcards to pay for things. In fact, many banks in Sweden no longer have cash on hand already.

A. The earliest paper money was the jiaozi. 

B. We are sure more and more people prefer to use paper money. 

C. By then, people will no longer use cash. 

D. Many countries use high tech to make online shopping not dangerous. 

E. Making fake (伪造的) money will become even harder. 

F. There are a few reasons for this. 

G. In China, paper money is getting less popular. 

Pencils and Pens

People have been eating apples for a very long time. When the first pioneers (拓荒者) came to America, there were only small, sour apples called crab apples. These apples were not good to eat. Later, pioneers brought apple seeds from their homes in Europe (欧洲).

In 1625 a man in Boston planted the first apple orchard (果园) in America. After that, when a pioneer family picked a place to live, they chose an area and planted apple seeds first. Soon, there were many apple trees in America.

The pioneers used apples in many ways. They made apple juice, apple butter, and apple pie. Sometimes they used apples as food for their animals. 

Today we have fridge and fruit shops. We have fresh fruits and vegetables even in winter. But the pioneers had no fresh fruits and vegetables during the long winters.

The pioneers soon learned how to preserve (保鲜) fruits and vegetables. They found that if they dried (使…变干) fruit, it would last and would not go bad. They could make apples last through the winter.

In autumn they picked the apples. Then many families would meet for a work party. They would talk and work at the same time. They peeled the apples and cut out the cores. Then they sliced (把…切片) the apples and laid them on a big net. About a week later, the apples were dried. They would keep for many months.

Dinosaurs used to be quite common on the earth. Then about 65 million years ago, most of them disappeared at nearly the same time. Although the mystery is still with us, there are many possible guesses. Here is one of them.

They were studying old layers (层) of rocks, which are about 65 million years old, when they suddenly found a kind of rare metal (稀有金属) in them. The metal has already been found in meteorites (陨石). And the scientists believe that it can be found in asteroids (小行星), too.

65 million years ago, a huge asteroid might hit the earth. Then wildfires broke out because of the hit. After the fires burned out, there was so much dust in the air that the sun could not shine through. For this reason, many plants could not grow. Plant-eating dinosaurs died too because they could not find enough food. Then meat-eating dinosaurs died, too.

The dust cloud may have hung over the earth for many months or even a year. Slowly it covered the ground, making the rock layers.

In 1908, something hit the earth in the forest of Siberia, a part of Russia. It broke millions of trees and caused fires. The object might be an asteroid.

Weekends, air conditioners (空调), takeouts… are all common things for modern people. Have you ever wondered if ancient people enjoyed the same lifestyles? Let's take a look.

During the Sui Dynasty, a terrible flood（洪水）happened on the Xiao River outside the city of Zhaozhou. The flood brought down a large stone bridge.

People had rebuilt the bridge several .

But it was still washed away over and over again. After the time that the bridge was destroyed, Li Chun was invited to solve the problem. " What's wrong with it? " Li Chun asked again and again. He worked day and night at the drawing of the bridge and found out the stone supports（支柱）couldn't stand the force of the flood.

One day, an idea came into his mind!He thought of building bow-shaped arches（拱）instead of stone supports. And there would be only one big arch, supported at each end by two small . floods came, the water would run through the four small arches, bringing little influence on the bridge. He was greatly excited by the idea, and danced right at his desk.

A new Zhaozhou Bridge was built. It was much and more beautiful than the old ones. The local people of Zhaozhou were very glad that the problem of the stone bridge was worked out. Now, this great stone bridge a history of over 1, 300 years has become a classical example of China's arched bridges. It shows the wisdom and creativity of the Chinese people.