On Sunday 23 April, more than 30, 000 people participated in the 2017 London Marathon, running 26.2 miles (42.2 kilometers) around the city centre.

    The London Marathon has taken place every year since 1981. At the first one just6,225 people completed the course, and since then it has grown into one of the biggest sporting events in the world. It is one of the “World Marathon Majors”, which is a competition made up of six global marathon events. The overall male and female winners receive $ 1 million in prize money between them. There are eleven people who have run every London Marathon since it began—they call themselves the “Ever Presents”.

    This year, the winners of the London Marathon were surprisingly both from Kenya— Daniel Wanjiru, who finished in 2 hours and 5 minutes, and Mary Keitany, whose time was 2 hours and 17 minutes.

    However, most marathon runners are not professional athletes. They are amateurs who have trained for months to raise money for charity or just as a personal challenge. For example, Tom Harrison took three days just to reach the run's halfway point, as he is crawling the course on his hands and knees dressed as a gorilla(大猩猩), trying to raise money and attention for the charity “The Gorilla Organization”.

    Matthew Rees was another runner to encourage people, as he stopped just before the finish line to help David Wyeth run the last 200m. They did not know each other before, but Matthew saw that David was exhausted and possibly close to collapsing, and wanted to help him finish.

    Every year there are lots of touching stories like this from the London Marathon, and it is a huge achievement even to run the 26.2 miles!

    Gravity signals that race through the ground at the speed of light could help seismologists(地震学家) get a better handle on the size of large, destructive quakes soon after they hit，a study suggests. The tiny changes in Earth's gravitational field, created when the ground shifts, arrive at earthquake monitoring stations well before earthquake waves.

    “The good thing we can do with these signals is have quick information on the magnitude (震级) of the quake,” says Martin Vaillée, a seismologist at the Paris Institute of Earth Physics.

    Earthquake equipment in China and South Korea picked up gravity signals immediately after the magnitude-9. 1 Tohoku earthquake that destroyed parts of Japan in 2011. The signals appear as tiny accelerations on earthquake-recording equipment, more than a minute before the seismic waves show up.

    “We can look before the earthquake waves arrive,” says Vallée. “If we see nothing, we can say that the quake that made these was maybe large, but not huge. If we see the signals, it means we really have a very big quake. ”

    Had seismologists been monitoring for gravity changes, they might have realized sooner just how big the Tohoku earthquake was. A small increase in an earthquake's magnitude means a large change in the energy released by the quake-and the destruction expected. That information is important for emergency responders as they decide what resources to arrange.

    It'll be a major contribution if gravitational waves can beat down the time needed to know that a big earthquake is big. But much work remains before gravity signals can be considered a reliable tool in the vital minutes after a big quake. A few extra minutes of warning can save lives, particularly in coastal areas where people can flee ahead of an incoming tsunami.

    Palaces are known for their beauty and splendor, but they offer little protection against attacks. It is easy to defend a large building, but usually these buildings are not designed with the comfort of a king in mind. When it comes to structures that are both beautiful and defensive, the European castle is a big success.

    Castles were originally built in England by the Normans in 1066. They built towers and walls to secure the land they had taken. These castles provided the Normans with a quiet and safe place. They also served as bases of operation for attacks. In this way castles served both defensive and offensive roles. Besides, castles served as offices for governors. Those that were socially beneath the governor would come to report affairs and express their respect. They would address problems, handle business, feast, and enjoy festivities in castles. So castles served as social centers as well.

    The first castles were made from earth and wood, and they were likely to suffer from attacks by fire. Then wooden castles were gradually replaced by stone, which greatly increased the strength of these towers and walls. However, attackers could throw flaming objects into castles through the windows or burn the wooden doors. This led to moving the windows and entrances off of the ground floor and up to the first floor to make them more difficult to access.

    During the Middle Ages, attacks increased in regularity, so castle defenses were updated. Arrow-slits were added. They were small holes in the castle, which allowed defenders to fire without being hurt. Towers were built from which defenders could provide fire on both sides. The towers were connected to the castle by wooden bridges, so that if one tower fell, the rest of the castle was still easy to defend. A lot of rings of castle walls were constructed, so that even if attackers went past one wall, they would be caught on a killing ground between inner and outer walls. All of these increased the defense of castles.

    The end of castles can be attributed to gunpowder. During the 15th century, artillery, a kind of large guns, became powerful enough to break through stone walls. This greatly made the role of castles less effective. Though castles no longer serve their original purposes, remaining castles receive millions of visitors each year who wish to experience the situations of ancient times.

    In March 2008, I told my friends: I was going to shut down my law practice and travel around the world in a year. What's more, I'd do it without taking any flights or making a single advance (预先的) reservation. Some friends offered support and encouragement, while others were doubtful. Once I'd said the words, there was no turning back. It took months to shut down my law practice and get things in order.

    There really wasn't any great reason why I wanted to circle the world. I simply wanted to do something fun and different. When I had this plan, I didn't plan for it to lead to a life on the road forever. I was planning to come back, open a new law practice and write a hugely successful book about my travels. Before I left, I started a travel blog, which served as a way to take notes for the book.

    Once I set off on my trip in December 2008, I found that travelling without using planes was not easy. It took seven days and nights on trains to get from Moscow to Beijing. Sometimes, I wouldn't see a village or a human being for 10 hours. I had a whole cabin to myself from the second day of that journey.

    It turned out that travelling with no reservations was far less difficult than I had imagined. Pulling into a city on a bus with a bag, looking in a guidebook for a few suggestions of accommodations (住宿), and then finding an empty room was never a problem.

    Soon after I started this adventure, I realised that my return to the US would be temporary (暂时的). About three months into my journey, I realised that I didn't want to go back to my old life. The world is so wonderful and I wanted to see as much of it as I could.

    The traditional British pub is part of the scenery of British life. At the last count, there are around 50,000 of them in the UK. The oldest – Ye Olde Fighting Cocks in St. Albans – was set up in about 793.

    Because of their abundance, the names pubs take are designed to be memorable, but more than that, they are designed to be visual. Outside any traditional pub worthy of its title, you'll find a hanging signboard with an unusual and uncommon illustration(插图) that represents the name of the business. The practice is so well established that even new pubs copy it. But why do they exist at all?

    The first British pub signs were created in the 12^th century and were simple representations of beer containers and other brewing-related equipment used to tell passersby that establishments sold beer. This was Britain in the dark ages, when education was in short supply. Since most of the population was unable to read, pub signs were used to inform would-be customers that they could find a drink inside.

    The earliest uses of pub names would reference the sign directly. People would appoint to meet at "the sign of the Eagle and Child" rather than at "the Eagle and Child".

    Today the tradition remains unchanged largely out of respect for the past, but many pub signs do have some functionality. Remote country pubs often use signboards to point the way to their doors. It's a part of British culture that's rapidly disappearing – more than 20,000 pubs have closed since 1980 – but for now there are still more than enough. You can take a moment to appreciate the history and symbolism behind a pub's sign the next time you see one.

A farmer grew some vegetables in his garden. One day his wife was ill and he had no money. He had to sell some cabbages and carrots in the market. The next morning he took two baskets of vegetables to town. But it was raining hard that afternoon and there were few people in the street. When his vegetables were sold out, it was dark. He bought some medicine and hurried to his village. 

On his way home he saw a person lying on the snow. He placed his baskets on the ground and was going to help the person to get up. At that time he found it was a dead man and there was much blood on his body. He was so afraid that he ran away quickly, without taking the baskets with him. 

The next afternoon the farmer was sent to the police station. Having shown the baskets, an officer asked: "Are these yours?" "Yes, sir." the farmer answered timidly (胆怯)."Have you killed the man?" "No, no, sir." the farmer said in a hurry. "When did you see the dead man?" "About seven last evening." "Did you see who killed the man?" "No, Sir." The officer brought out a knife and asked, "Have you seen it yet?" "No, Sir." The officer became angry and told the policemen to beat him up and send him into prison. 

That evening the officer went on trying. Pointing to the knife, he asked again, "Have you seen it yet?" "Yes, Sir." The officer was happy and asked, "When and where?" "I saw it here this afternoon, sir."