China is a land of bicycles. At least it was back in 1992 when I traveled the country. Back then everyone seemed to be riding a bicycle. Millions of them，all black. Cars were rare. Yet since my arrival in Beijing last year，I've found the opposite is true. There are millions of cars. However，people still use their bicycles to get around. For many，it's the easiest and cheapest way to travel today. Bicycles also come in different colors—silver，green，red，blue，yellow，whatever you want.

    It's fun watching people biking. They rush quickly through crossroads，move skillfully through traffic，and ride even on sidewalks（人行道）.Bicycles allow people the freedom to move about that cars just can't provide.

    Eager to be part of this aspect of Chinese culture，I decided to buy a bicycle. Great weather accompanied my great buy. I immediately jumped up on my bicycle seat and started home.

    My first ride home was orderly（守秩序的）．To be safe，I stayed with a “pack”of bikers while cars on the streets came running swiftly out of nowhere at times.I didn't want to get hit. So I took the ride carefully.

    Crossing the streets was the biggest problem. It was a lot like crossing a major highway back in the United States. The streets here were wide，so crossing took time，skill and a little bit of luck.

    I finally made it home. The feeling on the bicycle was amazing. The air hitting my face and going through my hair was wonderful. I was sitting on top of the world as I passed by places and people. Biking made me feel alive.

    Teachers' Day around the world is not celebrated on the same day. In some countries, Teachers' Day is celebrated on working days. However, in other countries, it is celebrated on holidays.

    Here we are giving you a list of countries that celebrate Teachers' Day on holidays.

China

    The Teachers' Day was proposed(提议) at National Central University in 1931. It was adopted(被采纳) by the central government of Republic of China in 1932. In 1939, the day was set on August 27th, Confucius's birthday. People's Republic of China government called it off in 1951. It was reestablished in 1985, and the day was changed to September 10th. Now more and more people are trying to celebrate the Teachers' Day back to Confucius's birthday.

India

    In India, Teachers' Day is celebrated on September 5th, in honor of Dr Sarvepalli Radhakrishnan, the second President of India. Because his birthday was September 5th. At schools on this day, students in India celebrate this day to show their respect and love to their teachers.

Russia

    In Russia Teachers' Day is on October 5th. Before 1994, this day was set on the first Sunday of September.

USA

    In the United States, Teachers' Day is a holiday on the Tuesday of the first full week of May.

Thailand

    January 16th was adopted as Teachers' Day in the Thailand by a resolution(决议) of the government on November 21, 1956. The first Teachers' Day was held in 1957.

Iran

    In Iran, Teachers' Day is celebrated on May 2nd every year. It is in honor of the famous Iranian professor Ayatollah Morteza Motahhari who died on May 2, 1980.

    Although different countries celebrate Teachers' Day on different days, the activities people take to celebrate it just stay the same.

    When was the last time you relied on an old-fashioned map to figure out the route to an unfamiliar place? For many, the GPS has revolutionized navigation, making a paper map almost obsolete? So how has this piece of technology developed over its 26 years of existence? On February 14,1989,the first satellite in the US Global Positioning System was sent into space from Cape Canaveral, beginning the start of one of the wonders of the modern world.

    GPS stands for Global Positioning System, which is made of a network of around 30 satellites that move around the earth. The system uses a process called trilateration to find out one's position. By measuring the time it takes for the signal to reach one satellite, the GPS can determine your distance from the satellite, creating a sphere(范围) of possible locations. Measuring your distance from at least three satellites will narrow your location to the place where the three spheres cross one another, to the accuracy(精确) of about less than 1 meter!

    The GPS was first invented during the Cold War by the United States Department of Defense. In 1960, the first system, which was made of just five satellites, was put into place. It was initially created for strictly military(军事的) use; however, in 1983, as a result of faulty navigation technology, a Korean passenger plane mistakenly flew into USSR territory(苏联领土) and was shot down. In order to prevent such bad events, American President Ronald Reagan allowed civilian(民用的) use of the GPS.

    Over the next ten years, the system's accuracy improved as the network was increased to 24 satellites. And during the first Persian Gulf War, the new GPS was finally used by the military. Now scientists use the technology to track animals to better understand their movement and behavior. Parents who may be worried about their children can also use GPS technology to track them.

    Before the coming of the first settlers from Europe, Canada's local people had discovered a new kind of food—maple sap(汁液)，which they gathered every spring. According to many historians, the maple leaf began to serve as a Canadian symbol as early as 1700.

    In 1834, the first St. Jean Baptise Society in North America made the maple leaf its sign. In 1836, Le Canadian, a newspaper, referred to it as a suitable symbol for Canada. In 1860, the maple leaf was used widely in decorations for the visit of the Prince of Wales. Alexander Muir wrote The Maple Leaf Forever in 1867; it was regarded as the national song for several decades. The army uniforms created the next year for Ontario and Quebec both included the maple leaf. Later the maple leaf appeared on coins. Between 1876 and 1901, it appeared on all Canadian coins. The modern one-cent piece has two maple leaves on a common twig(细枝)，a design that has gone almost unchanged since 1937.

    During the First World War, the maple leaf was included on the badge(徽章) of the Canadian Expeditionary Force. Since 1921, the Royal Arms of Canada have included three maple leaves as a special Canadian symbol. In 1939, at the time of World War Ⅱ, many Canadian troops used the maple leaf as a special sign.

    With the announcement of Canada's new flag in 1965, the maple leaf has become the Canadian symbol. On February 15 of that year, the red maple leaf flag first appeared as the National Flag of Canada.

    There are some very good things about open education. This way of teaching allows the students to grow as people, and to develop their own interests in many subjects. Open education allows students to be responsible for their own education, as they are responsible for what they do in life. Some students do badly in a traditional classroom. The open classroom may allow them to enjoy learning. Some students will be happier in an open education school. They will not have to worry about grades or rules. For students who worry about these things a lot, it is a good idea to be in an open classroom.

    But many students will not do well in an open classroom. For some students, there are too few rules. These students will do little in school. They will not make good use of open education. Because open education is so different from traditional education, these students may have a problem getting used to making so many choices. For many students it is important to have some rules in the classroom. They worry about the rules even when there are no rules. Even a few rules will help this kind of students. The last point about open education is that some traditional teachers do not like it. Many teachers do not believe in open education. Teachers who want to have an open classroom may have many problems at their schools.

    You now know what open education is. Some of its good points and bad points have been explained. You may have your own opinion about open education. The writer thinks that open education is a good idea, but only in theory. In actual fact, it may not work very well in a real class or school. The writer believes that most students, but of course not all students, want some structure in their classes. They want and need to have rules. In some cases, they must be made to study some subjects. Many students are pleased to find subjects they have to study interesting. They would not study those subjects if they did not have to.

How Much Can We Afford to Forget?

    In 2018, Science magazine asked some young scientists what schools should teach students. Most said students should spend less time memorizing facts and have more space for creative activities. As the Internet grows more powerful, students can access(获得)knowledge easily. Why should they be required to carry so much of it around in their heads?

    Civilizations(文明)develop through forgetting life skills that were once necessary. In the Agricultural(农业的)Age, a farmer could afford to forget hunting skills. When societies industrialized, the knowledge of farming could be safe to forget. Nowadays, smart machines give us access to most human knowledge. It seems that we no longer need to remember most things. Does it matter?

    Researchers have recognized several problems that may happen. For one, human beings have biases (偏见), and smart machines are likely to increase our biases. Many people believe smart machines are necessarily correct and objective, but machines are trained through a repeated testing and scoring process. In the process, human beings still decide on the correct answers.

    Another problem relates to the case of accessing information. When there were no computers, efforts were required to get knowledge from other people, or go to the library. We know what knowledge lies in other brains or books, and what lies in our heads. But today, the Internet gives us the information we need quickly. This can lead to the mistaken belief — the knowledge we found was part of what we knew all along.

    In a new civilization rich in machine intelligence, we have easy access to smart memory networks where information is stored. But dependency on a network suggests possibilities of being harmed easily. The collapse of any of the networks of relations our well-being(健康)depends upon, such as food and energy, would produce terrible results. Without food we get hungry; without energy we feel cold. And it is through widespread loss of memory that civilizations are at risk of falling into a dark age.

    We forget old ways to free up time and space for new skills. As long as the older forms of knowledge are stored somewhere in our networks, and can be found when we need them, perhaps they're not really forgotten. Still, as time goes on, we gradually but unquestionably become strangers to future people.