Teachers' Day is, interestingly, not celebrated on the same day all over the world. In some countries it is marked by a holiday, in others it is a working day.

    International Teachers' Day is celebrated on October 5. Being held ever since 1994, it is in honor of teachers' organizations worldwide. Its aim is to encourage supports for teachers and to meet the needs of students.

    China    In 1939, Teachers' Day was set for August 27, Confucius' birthday. In1951, the celebration was stopped. However, it was founded again in 1985, and the day was changed to September 10.

    India     Teachers' Day is celebrated on September 5 in honour of Dr. Sarvepalli Radhakrishnan, the second president of India, whose birthday falls on that day.

    Russia    In Russia, Teachers' Day was celebrated on the first Sunday of October between 1965 and 1994. Since 1994, the day is observed on the October 5, just the same day as World Teachers Day.

    The US    In the US, Teachers' Day is non-official holiday. It is celebrated on the Tuesday of the first full week of May. A number of activities are organized in schools to honor teachers. The celebrations can continue for the whole week of May.

    Thailand     In Thailand, National Teachers' Day is celebrated every year on January 16. The first Teachers' Day was held in 1957. The day is a holiday in schools.

    North America tours

    Tour North America and discover how the New World became the culturally diverse civilization it is today: the world's greatest melting pot is in your own backyard.

Boston: Colonial History

    Days: 4

    Get your walking shoes ready to follow the footsteps of the American Founding Fathers in Boston. Journey through the landmarks of the American Revolution in this historical city by walking down the Freedom Trail with a Colonial tour guide. Get out of the city with detours to Salem. Lexington, Concord and Plymouth, where you will see where the first shots of the American Revolution were fired.

Civil Rights in the South

    Days: 5

    Journey back to a time of revolution and brotherhood in the heart of the Civil Rights Movement. Follow the path of the marches through Atlanta, Montgomery and Birmingham, as well as the town of Selma, where a peace l protest erupted into what is now called" Bloody Sunday. "Pay respect to the key contributors to civil rights by visiting the Rosa Parks Museum and the home and church of the most famous civil rights activist of them all. Dr Martin Luther King, Jr.

    IL MUNC in Philadelphia

    Days: 4

    The Ivy League Model UN Conference (ILMUNC) is known as a unique educational experience for its focus on international affairs and networking. Students from across the continent will come together to debate and discuss pressing global issues as UN delegates. You can also explore some of downtown Philadelphia's finest attractions including the Philadelphia Museum of Art, the Liberty Bell. Independence Hall before or after the conference.

    Quebec City &Montreal Four Day Spring Tour

    Days: 4

    Montreal and Quebec City are two of the most diverse, beautiful and exciting travel destinations in Canada. Your tour through Quebec's Upper Town includes the beautifully lit National Assembly, Dufferin Terrace, and Chateau Frontenac. Walk along the 17^th-century cobblestone streets of Lower Town, then continue on to Montreal for a visit to Mont Royal, which boasts breathtaking views from the highest point in the cit.

    NOT all memories are sweet. Some people spend all their lives trying to forget bad experiences. Violence and traffic accidents can leave people with terrible physical and emotional scars. Often they relive these experiences in nightmares.

    Now American researchers think they are close to developing a pill, which will help people forget bad memories. The pill is designed to be taken immediately after a frightening experience. They hope it might reduce ,or possibly erase(抹去),the effect of painful memories.

    In November, experts tested a drug on people in the US and France. The drug stops the body releasing chemicals that fix memories in the brain. So far the research has suggested that only the emotional effects of memories may be reduced, not that the memories are erased.

    The research has caused a great deal of argument. Some think it is a bad idea, while others support it.

    Supporters say it could lead to pills that prevent or treat soldiers' troubling memories after war. They say that there are many people who suffer from terrible memories.

    "Some memories can ruin people's lives. They come back to you when you don't want to have them in a daydream or nightmare. They usually come with very painful emotions," said Roger Pitman, a professor of psychiatry at Harvard Medical School. "This could relieve a lot of that suffering."

    But those who are against the research say that changing memories is very dangerous because memories give us our identity (特质). They also help us all avoid the mistakes of the past.

    "All of us can think of bad events in our lives that were horrible at the time but make us who we are. I'm not sure we want to wipe those memories out, "said Rebecca Dresser, a medical ethicist.

    Throughout much of human history, man has been the measure of many, if not all, things. Lengths were divided up into feet and smaller units from the human hand. Other measures were equally characteristic. Mediterranean traders for centuries used the weight of grains of wheat to define (定义) their units of mass. The Romans used libra, forerunner of the pound, by referring to the weight of a carob (角豆树) seed.

    The sizes of similarly named units could also differ. The king's foot, used in France for nearly

    1,000 years after its introduction by Charlemagne in around 790 AD, was, at 32.5cm,around a centimeter shorter than the Belgic foot, used in England until 1300.Greek,Egyptian and Babylonian versions of water in a fixed container varied from one another by a few kilos, Nor was there agreement on such things within countries. In France, where there was no unified (统一的) measurement system at the national level, the situation was particularly terrible. The lieue (former measure of distance), for example, varied from just over 3 km in the north to nearly 6 km in the south.

    Although John Wilkins, an Englishman, first put forward a decimal system (十进制) of measurement in 1668,it was the French who in 1799 made it law. The Système International d'Unités (SI, or the metric system, as it is better known) developed from it and became the official measurement in all countries except Myanmar, Liberia and the United States. Now the International Bureau of Weights and Measures in Paris is set to give the metric system its biggest shake-up yet.

    At a meeting in Versailles, France, on November 16th,2018,the world's measurement bodies are almost certain to approve a decision that will mean four out of the seven base SI units, including the kilogram, will follow the other three, including the metre, in being redefined in terms of the values of physical constants (物理常数).Each of the chosen constants has been measured incredibly precisely, which would mean that from May 20^th 2019 the constants will themselves be fixed at their current values for ever. Any laboratory in the world will then be able to measure, for example, the mass of an object as precisely as the accuracy of their equipment will allow.

    You are a member in a full-time school called "life". Each day here you will have the opportunity to learn lessons. You may like the lessons or hate them, but you have designed them as part of your curriculum.

    Why are you here? What is your purpose? Humans have sought to discover the meaning of life for a very long time. What we and our ancestors have to overlook is that there is no one answer. The meaning of life is different for every individual.

    Each person has his own purpose and distinct path, unique and separate from anyone else's. As you are traveling your life path, you will be presented with numerous lessons you will need to learn in order to achieve that purpose. The lessons you are presented with are specific to you; learning these lessons is the key to discovering and achieving the meaning of your own life.

    As you are traveling through your lifetime, you may meet challenging lessons that others don't have to face, while others spend years struggling with challenges that you don't need to deal with. You may never know why you are blessed with a wonderful marriage, while your friends suffer painful divorces, just as you cannot be sure why you struggle financially while your peers enjoy abundance. The only thing you can count on is that you will be presented with all the lessons that you specifically need to learn.

    The challenge, therefore, is to arrange yourself with your own unique path by learning individual lessons. This is one of the most difficult challenges you will face in your lifetime, as sometimes your path will be different from others. But don't compare your path with that of people around you and focus on the differences between their lessons and yours. You need to remember that you will only face lessons that you can learn and are specific to your own growth.

    Our sense of fairness is the expectation of equality. Life is not, in fact, fair, and you may indeed have a more difficult life path than others around you, deserved or not. Everyone's circumstances are unique, and everyone needs to handle his or her own circumstances differently.

We were about to gather up our things and return to our car when a man came up.He looked very 1 indeed and asked us 2 if we knew that these grounds were his own.Father looked troubled and the man 3 a notice,which said that camping was strictly 4 .My poor father explained that he had not seen the 5 and did not know that camping was not allowed.6 Father apologized,the man did not seem satisfied.He asked Father for his name and 7 .All the way home,we were so 8 that hardly anyone said a word.This 9 thing had spoiled(损害)a wonderful day in the country.

For the rest of the week,we 10 what would happen.The following Sunday,we stayed at home even though it was a 11 day.About noon,a large and very expensive 12 stopped outside our house.We were surprised when we saw several people preparing to have a picnic in our small 13 .Father got very 14 and went to ask them what they thought they were doing.You can imagine how 15 he was when he saw the man who had taken our address the week before!Both men burst out 16 and Father welcomed the strangers into the house.We became good 17 .And we learned a lesson we have never 18 .That's "Don't do to others 19 you don't like to 20 to you."