A good joke can be the hardest thing to understand when studying a foreign language. As a recent article in The Guardian newspaper noted, “There's more to understanding a joke in a foreign language than understanding vocabulary and grammar.”

    Being able to understand local jokes is often seen as an unbelievable ice-breaker for a language learner eager to form friendships with native speakers. “I always felt that humor was a ceiling that I could never break through,” Hannah Ashley, a public relations account manager in London, who once studied Spanish in Madrid, told The Guardian, “I could never speak to people on the same level as I would speak to a native English speaker. I almost came across as quite a boring person because all I could talk about was facts.”

    In fact, most of the time, jokes are only funny for people who share a cultural background or understand humor in the same way. Chinese-American comedian Joe Wong found this out first-hand. He had achieved huge success in the US, but when he returned to China in 2008 for his first live show in Beijing, he discovered that people didn't think his. Chinese jokes were as funny as his English ones.

    In Australia, meanwhile many foreigners find understanding jokes about sports to be the biggest headache. “The hardest jokes are related to rugby because I know nothing about rugby,” said Melody Cao, who was once a student in Australia. “When I heard jokes I didn't get, I just laughed along.”

    In the other two major English-speaking countries, the sense of humor is also different. British comedian Simon Pegg believes that while British people use irony (反话)—basically, saying something they don't mean to make a joke—every day, people in the US don't see the point of using it so often. “British jokes tend to be more subtle and dark, while American jokes are more obvious with their meanings, a bit like Americans themselves,” he wrote in The Guardian.

    In 1905, as part of his Special Theory of Relativity, Albert Einstein published the point that a large amount of energy could be released from a small amount of matter. This was expressed by equation E = me 2(energy = mass times the speed of light squared). But bombs were not what Einstein had in mind when he published this equation.

    In 1929, he publicly declared that if a war broke out he would “refused to do war service, direct or indirect…” His position would change in 1933, as the result of Adolf Hitler's coming into power in Germany.

    Einstein's greatest role in the invention of the atomic bomb was signing a letter to President Franklin Roosevelt urging that the bomb be built because some physicists feared that Germany might be working on an atomic bomb. Among those concerned were physicists Leo Szilard and Eugene Wigner. But Szilard and Wigner had no influence with those in power. So in July 1939 they explained the problem to someone who did: Albert Einstein. After talking with Einstein, in August 1939 Szilard wrote a letter to President Roosevelt with Einstein's signature on it, which was delivered to Roosevelt in October 1939.

    Germany has invaded Poland the previous month; the time was ripe for action. That October research of a-bomb began but proceeded slowly because the invention of the atomic bomb seemed distant and unlikely. In April 1940 an Einstein letter, ghost-written by Szilard, pressed the researchers on the need for “greater speed”.

    As the realization of nuclear weapons grew near, Einstein looked beyond the current war to future problems that such weapons could bring. He wrote to his friend about his fear about the future use of the a-bomb.

    The atomic bombings of Japan occurred three months after Germany gave in.

In November 1954, five months before his death, Einstein summarized his feelings about his role in the creation of the atomic bomb: “I made one great mistake in my life… when I signed a letter to President Roosevelt recommending that atom bombs be made; but there was some justification—- the danger that the Germans would make them”.

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    When we think of leadership, we often think of strength and power. But what are these really, and how do they operate?

    Leadership today is not about forcing others to do things. If this is even possible, it is short-term. If you order someone to do something against their will, they may do it because they feel they must, but the anger they feel will do more harm in the long-term. They will also experience fear.

    Fear causes the thinking brain to shut down, making the person unable to function at his or her best. If they connect you with this emotion of fear, they will become less functional around you, and you will have succeeded in not only shooting yourself in the foot, but possibly making a very good employee or partner unable to perform effectively. Fear has no place in leadership.

    The way we affect people in a lasting way is by our own character, and our understanding and use of emotion. We can order someone to do something, which may be part of the work day, or we can employ them at the emotional level, so they become fully devoted to the projects and provide some of their own motivation (积极性). Today's work place is all about relationships.

    Anyone works harder in a positive environment in which they're recognized and valued as a human being as well as a worker. Everyone produces just a bit more for someone they like Leaders understand the way things work. They know money is not the only most motivating factor in the work life of most people.

    The true strength of leadership is an inner strength that comes from the confidence of Emotional Intelligence—knowing your own emotions, and how to deal with them and those of others. Developing your emotional intelligence is the best thing you can do if you want to develop your relationships with people around you, which is the key to the leadership skills.

    The Pew report—which was based on surveys carried out in Britain, France, Germany, Italy, Spain, Greece, Poland and the Czech Republic—concluded that the European Union was “ the new sick man of Europe”.

    The percentage of Europeans with a favorable view of the EU has plunged from 60 percent last year to 45 percent now.

    The UK may be considered the most Eurosceptic（欧洲怀疑论者）country, but its support for the union has barely changed in the past 12 months, slipping only two points to 43 percent.

    By contrast, France's backing for the EU has slipped sharply, from 60 percent last year to 41 percent today.

    On the question of whether to remain in the EU, 46 percent of the British want to leave the union and surprisingly, the same percentage want to stay.

    The Pew report's authors said, “The long-drawn economic crisis has created bad forces that are pulling European public opinion apart, separating the French from the Germans and Germans from everyone else.”

    They added, “The effort over the past half century to create a more united Europe is now the main disaster of the euro crisis. The European project now stands in a bad reputation across much of Europe.”

    The only European leader rated highly by their own voters was the German Chancellor Angela Merkel, with 74 percent voters in favor of her.

    Prime Minister David Cameron was the next highest with a positive score of 37 percent among the British public, although he can take some comfort from the fact that 58 percent of Poles（波兰人）and half of all French people think he is doing a good job.

    In spite of the dark economic future and growing doubt of the EU, there were strong majorities of more than 60 percent in favor of keeping the euro in the five countries surveyed that use the single currency.

    The idea of turning recycled plastic bottles into clothing is not new. During the last five years, a large number of clothing companies, businesses and environmental organizations have started turning plastics into fabric to deal with plastic pollution. But there's a problem with this method. Research now shows that microfibers could be the biggest source of plastic in the sea.

    Dr. Mark Browne in Santa Barbara, California, has been studying plastic pollution and microfibers for 10 years now. He explains that every time synthetic (合成的)clothes go into a washing machine, a large number of plastic fibers fall off. Most washing machines can't collect these microfibers. So every time the water gets out of a washing machine, microfibers are entering the sewers and finally end up in the sea.

    In 2011, Browne wrote a paper stating that a single piece of synthetic clothing can produce more than 1, 900 fibers per wash. Browne collected samples from seawater and freshwater sites around the world, and used a special way to examine each sample. He discovered that every single water sample contained microfibers.

    This is bad news for a number of reasons. Plastic can cause harm to sea life when eaten. Studies have also shown that plastic can absorb other pollutants.

    Based on this evidence, it may seem surprising that companies and organizations have chosen to turn plastic waste into clothing as an environmental "solution." Even though the science has been around for a while, Browne explains that he's had a difficult time getting companies to listen. When he asked well-known clothing companies to support Benign by Design—his research project that seeks to get clothes that have a bad effect on humans and the environment out of the market, Browne didn't get a satisfying answer. Only one women's clothing company, Eileen Fisher, offered Browne funding.

    Researchers have discovered the first Earth-sized planet. It was first marked by scientists' using NASA's Kepler telescope (望远镜), so it's called Kepler﹣186f. It lies about 500 light years from Earth and goes around its star. The planet is the right distance from its star for water: not too close or not too far. Water is one important condition that scientists guess is necessary for life. So it could have water and possible life. It's called a true Earth cousin.

    "This planet is an Earth cousin, not an Earth twin," said Barclay, who is among a team of scientists reporting on the discovery in the magazine Science this week.

    "It's very exciting to find a planet similar to the Earth," Barclay said. "It's not easy work because things change as we get more measurements."

    Scientists don't know anything about the air of Kepler-186f, but it will be a task for future telescopes which can study for chemicals that have something to do with life.

    "It's possible for life to live in this planet, but that doesn't mean there is life in it," Barclay said.

    So far, scientists have found nearly 1,800 planets in the universe.

    "The past year has seen a lot of progress in the search for Earthlike planets. Kepler﹣186f is very important because it is the first planet that is the same temperature and is almost the same size as Earth," scientist David Charbonneau wrote in an email.