In colonies (群体) that range in size from a few hundred to tens of millions, they organize their lives with a clear division of labor. Even more amazing is how they achievethis level of organization. Where we use sound and sight to communicate, ants dependprimarily on pheromone (外激素), chemicals sent out by individuals and smelled or tastedby fellow members of their colony. When an ant finds food, it produces a pheromone that will lead others straight to where the food is. When an individual ant comes under attack or is dying, it sends out an alarm pheromone to warn the colony to prepare for a conflict as a defense unit.

         In fact, when it comes to the art of war, ants have no equal. They are completely fearless and will readily take on a creature much larger than themselves, attacking in large groups and overcoming their target. Such is their devotion to the common good of the colony that not only soldier ants but also worker ants will sacrifice their lives to help defeat an enemy.

         Behaving in this selfless and devoted manner, these little creatures have survived on Earth, for more than 140 million years, far longer than dinosaurs. Because they think as one, they have a collective (集体的) intelligence greater than you would expect from itsindividual parts.

    Given that many people 's moods(情绪)are regulated by the chemical action of chocolate, it was probably only a matter of time before somebody made the chocolate shop similar to a drugstore of Chinese medicine. Looking like a setting from the film Charlie& the Chocolate Factory, Singapore's Chocolate Research Facility (CRF) has over 100 varieties of chocolates. Its founder is Chris Lee who grew up at his parents' comer store with one hand almost always in the jar of sweets.

    If the CRF seems to be a smart idea, that's because Lee is not merely a seasoned salesperson but also head of a marketing department that has business relations with big names such as Levi's and Sony. That idea surely results in the imagination at work when it comes to making different flavored (味道)chocolates.

    The CRF's produce is “green” made within the country and divided into10 lines, with the Alcohol Series being the most popular. The Exotic Series—with Sichuan pepper, red bean (豆), cheese and other flavors also—does well and is fun to taste. And for chocolate snobs, who think that they have a better knowledge of chocolate than others, the Connoisseur Series uses cocoa beans from Togo, Cuba, Venezuela , and Ghana, among others.

    Friends play an important role in our lives, and although we can't be more familiar with the fact of friendship, we often don't clearly understand how we make friends, especially with Americans. Here are some pieces of advice on making friends with Americans:

    ⒈Visiting places Americans enjoy: parties, churches, restaurants, parks and sports clubs.

    ⒉Be willing to take the first step. Don't wait for them to get close to you. Americans in China may not know you speak English. They may be uncomfortable if they can't speak your language.

    ⒊Use small talks to open the conversation. Ask them where they're from, why they come to China, etc.. Remember: Be careful not to ask personal questions about age, salary and so on.

    ⒋Show an interest in their culture, their country or their job. Americans like to talk about themselves!

    ⒌Invite them to join you for dinner or just for coffee or tea. Try to set a specific(明确的)time. Americans sometimes make general invitations like “Let's go out for dinner sometime. ” Often this is just a way to be friendly. It is not always a real invitation.

    ⒍Don't expect too much at first. Maybe they're being friendly. But maybe they want to be your good friends. It will take time to tell.

    Most people who fly on passenger planes in the United States do not lose their luggage. Even if the luggage is lost, usually it is only delayed. Most "lost" luggage is found in a few days. Airlines search for the owners of unclaimed(未认领的) bags for up to three months. But when the owners cannot be found or the bags are not claimed, they are sold to a store in the small city of Scottsboro, in the southern state of Alabama.

    About one-half of one percent of all luggage passing through US airports is unclaimed. Many of the missing bags, and what is in them, are sold at the Unclaimed Baggage Center. Seven thousand items arrive at the store every day. Tom Barnes, who was shopping at the store said, "I can go into any of the large shopping centers, like the international malls. I can walk through there for an hour and come out with three items. But I come into this store, and then I come out with my car full of stuff."

    Brenda Cantrell, who works at the store, said, "The Unclaimed Baggage Center is the only store in America that buys and resells unclaimed baggage from the airline industry. You would be surprised at all the jackets, eyeglasses, neck pillows, blankets, laptops, Kindles, iPads, and you know, all kinds of expensive electronics."

    The store says it once sold a container for flowers for $80 that was found to be worth $18,000. And it says a painting it sold for $25 was later found to be worth $25,000.

    The store buys the luggage from the airlines. It does not examine the things inside them before buying them. Only about half of the items in the bags are suitable for sale at the store.

    Some people say it is not fair to the owners of the lost passage to sell their goods. Customer Daniel Martin is not one of them, saying, "I feel the airport may try to find the people that lose the things. If they've tried and they can't get a hold of them, it's better than throwing them away or just letting them rot in a warehouse somewhere."

    The World Happiness Report, a United Nations agency report, measures (估量) how happy people are, and why. Norway is the happiest place on earth—beating neighbour Denmark from the number one position.

    Denmark, Iceland, Switzerland and Finland are among the top five, while the Central African Republic came last. Western Europe and North America took up most of the places at the top of table, with the US and UK at 14th and 19th respectively.

    The World Happiness Report mainly depends on asking a simple question of more than 1,000 people every year in more than 150 countries. “Imagine a ladder, with steps numbered from 0 at the bottom to 10 at the top,” the question asks. “The top of the ladder is the best possible life for you and the bottom of the ladder is the worst possible life for you. On which step of the ladder would you say you personally feel you stand at this time?”

    The average (平均的) result is the country's score—from Norway's 7.54 to the central African Republic's 2.69. But the report also tries to explain why one country is happier than another. It looks at reasons including economic strength, social support, freedom of choice, and generosity.

    This year's report also has a text titled “restoring (恢复) American happiness”, which examines why happiness levels in the United States are falling, despite continually-increasing economic improvement. “The United States can and should raise happiness by solving American's social problems—rising inequality and distrust—rather than focusing mainly on economic growth,” the authors said.

    Jeffrey Sachs, the director of the Sustainable Development Solutions Network, which published the report, said President Donald Trump's policies were likely to make things worse.

    I always felt sorry for the people in wheelchairs. Some people, old and weak, cannot get around by themselves. Others seem perfectly healthy, dressed in business suits. But whenever I saw someone in a wheelchair, I only saw a disability，not a person.

    Then I fainted(昏倒) at Euro Disney due to low blood pressure. This was the first time I had ever fainted, and my parents said that I must rest for a while after first aid. I agreed to take it easy, but as I stepped toward the door, I saw my dad pushing a wheelchair in my direction! Feeling the colour burn my cheeks, I asked him to wheel that thing right back to where he found it.

    I could not believe this was happening to me. Wheelchairs were fine for other people but not for me. As my father wheeled me out into the main street, people immediately began to treat me differently.

    Little kids ran in front of me, forcing my father to stop the wheelchair suddenly. Bitterness set in as I was thrown back and forth.

    "Stupid kids! They have perfectly good legs. Why can't they watch where they are going？"I thought. People stared down at me，pity in their eyes. Then they would look away, maybe because they thought the sooner they forgot me the better. "I'm just like you!" I wanted to scream "The only difference is that you've got legs，and I have wheels."

    People in wheelchairs are not stupid. They see every look and hear each word. Looking out at the faces, I finally understood: I was once just like them. I treated people in wheelchairs exactly the way they did not want to be treated. I realized it is some of us with two healthy legs who are truly disabled.