【推荐3】At many Thanksgiving dinners, everyone around the table shares something they are thankful for. As we know, most can do this easily. It's more important to know how to be thankful people all the time.

Be positive(乐观). No matter what happens, it's best to remember the good things. Find the bright side in bad situations, and push back against negative(负面的) opinions. Also, do your best not to compare yourself to others. But when you're around others, give expression to what you like about them. By keeping good in mind, you'll gibe thanks for it even more than before.

Accept the negative. At the same time, we can't pay no attention to bad things that have happened. We should learn from mistakes. （A）It makes us become strong. Before we know it, we're thankful for negative things, too. Our mistakes can also make us humble(谦逊的), which is not all bad. Humble people have better relationships and see life's blessings(祝福) much more clearly!

Acts of kindness. Thankful people know that it's much better to gibe than to receive. When you're thankful, you feel it's your duty to show love to others. Some people volunteer to help people in need. Studies show that volunteers might feel happier and healthier.

Use of time. By spending time with others, you show them how much they mean to you. But being thankful is also better realized by spending time alone. （B）When you're alone, you can think about the best parts of you day. You can list them out and think them over. You can find your way to make thanksgiving a part of your life. How wonderful it is! Just enjoy it every day!

【推荐1】Once thirty thousand years ago, people from northern Asia went to America. Today, we call these people Indians.

The Indians went to America because the weather began to change. Northern Asia became very cold. Everything froze. They had to move or die. How did the first Indians go to America?   They walked!

Later Columbus found the New World in 1492. At first, only a few Europeans followed. They traveled to America in boats. For the next three hundred years, about 500, 000 people went there. Then the number grew very quickly. From 1815 to 1915, over thirty-two million Europeans left their countries and went to the United States. The biggest groups were from Germany and Italy. These Europeans spoke many different languages. Most of them took almost no money. They went to America so that they could find a better life.

Throughout history, most masks are made to change identity. Medical masks, on the other hand, are meant to protect. Here is a brief history of their evolution.

17th century

Doctors wore a uniform that included a headdress with a long, pointed beak filled with aromatics(芳香料) to stop bad smell and fight against contagion(传染) carried by bad air. The historical mask is on show in a museum in Berlin.

19th century

In an article in Scientific American in 1878, A. J. Jessup, a New York physician, recommended cotton masks to limit contagion during epidemics (widespread of a disease). However, his idea did not catch on.

Early 20th century

Researchers published the first study encouraging the use of medical masks in 1897, but they were uncommon at the turn of the century.

In 1905, Chicago physician Alice Hamilton published an article in the Journal of the American Medical Association. "A student in a large medical college in Chicago told me that when the doctor talked to others during an operation, he could see a spray of saliva(唾液) coming from the mouth of the doctor," Alice Hamilton wrote, "so masks should be worn by doctors and nurses in every operation."

During the 1918 global flu, medical workers usually wore masks to protect themselves, and many cities required masks in public. In Seattle, streetcars required all riders to have masks.

In the 1920s, masks became standard in operating rooms. Over the next century, medical researchers went on with experiment on designs and materials of masks.

Post-World WarⅡ

Because of the heavy air pollution, Britons had to wear "smog masks". As developed countries cleaned up their pollution, smog and smog masks moved to developing countries. Mask models such as N95 and KN90 became highly popular.

As we can see, masks have been helping mankind for centuries. Wearing medical masks is widely believed to be an easy but effective method to protect oneself from different kinds of harmful things.

The Silk Road is the name of different roads that long ago linked Europe, Africa and Asia.

People reached these different places along these roads. Scientists and archaeologists（考古学家） believe people began to travel the Silk Road about 3,000 years ago. By the time the Chinese silk trade became important in the world, the Silk Road had covered almost 6,500 kilometers. It stretched from Rome to China, which is from the West to the Far East.

Businessmen travelling along the Silk Road carried silk, of course. They also carried and traded spices, cloth, rare jewels, slaves and gold.

During its busiest period, the Silk Road allowed people from many different cultures and countries to meet each other and mix. The Silk Road allowed the sharing of precious goods and new ideas. These included people and trading goods from the Mediterranean, Persian, Magyar, Armenian, Bactrian, Indian and Chinese areas. All these peoples travelled the Silk Road, and they shared goods, stories, languages and cultures.

In modern times, the old Silk Road routes（路线） are still used, but now they are crossed by trains instead of camels and horses. There is even a Silk Route Museum in Jiuquan in China. It has over 35,000 objects from all along the Silk Road. In this way, China protects（保护） the history of many countries and peoples. Seeing is believing. If you have a chance, please go to have a walk and have a look.