The Asian country announced yesterday that China was putting tariffs or taxes on about $3 billion worth of imports from the U.S. The tariffs are on 128 American-made products, ranging from pork and fruit to steel pipes. This will make it more expensive for America businesses to sell those products in China. And China says this was done as a response to the tariffs that the U.S. recently put on imports of Chinese steel and aluminum.

    Meanwhile, U.S. President Donald Trump says more tariffs, new ones worth as much a $50 billion are being planned by the U.S. on additional goods from China. So, one big question is, will all this cause a trade war, when countries take turns putting tariffs on each other 's goods, causing prices to rise?

    We don't know yet. The U.S. and China ship hundreds of billions of dollars of goods back and forth every year. So, the tariffs we've seen so far are a tiny part of that. And America's treasury secretary says the U.S. and China are talking behind the scenes about how to prevent a possible trade war.

    But a number of experts are concerned this could turn into one and so are some stock investors. The Chinese tariffs were a major factor in a drop of the U.S. stock market yesterday when the Dow Jones Industrial Average fell 459 points. But just like it's hard to tell if a trade war is on the horizon, it's also hard to tell what kind of effects one could have decades down the road.

    Being sociable looks like a good way to add years to your life. Relationships with family, friends, neighbours, even pets, will all do the trick, but the biggest longevity(长寿) boost seems to come from marriage or an equivalent relationship. The effect was first noted in 1858 by William Farr, who wrote that widows and widowers(鳏夫) were at a much higher risk of dying than their married peers. Studies since then suggest that marriage could add as much as seven years to a man's life and two to a woman's. The effect holds for all causes of death, whether illness, accident or self-harm.

    Even if the odds are stacked against you (the conditions are not favourable), marriage can more than compensate. Linda Waite of the University of Chicago has found that a married older man with heart disease can expect to live nearly four years longer than an unmarried man with a healthy heart. Likewise, a married man who smokes more than a pack a day is likely to live as long as a divorced man who doesn't smoke. There's a flip side, however, as partners are more likely to become ill or die in the couple of years following their spouse's death, and caring for a spouse with mental disorder can leave you with some of the same severe problems. Even so, the odds favour marriage. In a 30-year study of more than 10,000 people, Nicholas Christakis of Harvard Medical School describes how all kinds of social networks have similar effects.

    So how does it work? The effects are complex, affected by socio-economic factors, health-service provision, emotional support and other more physiological mechanisms(机制). For example, social contact can boost development of the brain and immune system, leading to better health and less chance of depression later in life. People in supportive relationships may handle stress better. Then there are the psychological benefits of a supportive partner.

    A life partner, children and good friends are all recommended if you aim to live to 100.The best social network is still being mapped out, but Christakis says: “People are interconnected, so their health is interconnected.”

Larry was on another of his underwater expeditions(探险)but this time, it was different. He decided to take his daughter along with him. She was only ten years old. This would be her first trip with her father on what he had always been famous for.

    Larry first began diving when he was his daughter's age. Similarly, his father had taken him along on one of his expeditions. Since then, he had never looked back. Larry started out by renting diving suits from the small diving shop just along the shore. He had hated them. They were either too big or too small. Then, there was the instructor. He gave him a short lesson before allowing him into the water with his father. He had made an exception. Larry would never have been able to go down without at least five hours of theory and another similar number of hours on practical lessons with a guide. Children his age were not even allowed to dive.

After the first expedition, Larry's later diving adventures only got better and better. There was never a dull moment. In his black and blue suit and with an oxygen tank fastened on his back, Larry dived from boats into the middle of the ocean. Dangerous areas did not prevent him from continuing his search. Sometimes, he was limited to come to a cage underwater but that did not bother him. At least, he was still able to take photographs of the underwater creatures.

    Larry's first expedition without his father was in the Cayman Islands. There were numerous diving spots in the area and Larry was determined to visit all of them .Fortunately for him, a man offered to take him around the different spots for free. Larry didn't even know what the time was, how many spots he dived into or how many photographs he had taken. The diving spots afforded such a wide array of fish and sea creatures that Larry saw more than thirty varieties of creatures.

Larry looked at his daughter. She looked as excited as he had been when he was her age. He hoped she would be able to continue the family tradition. Already, she looked like she was much braver than had been then. This was the key to a successful underwater expedition.

    The other day I was shopping at the local Chinese grocery store. There was a line at the fish counter, but only one staff person was there to take care of the customers. Some customers ordered quite an amount of fish for that staff person to work on. At last I was the second in line; all I wanted was a couple of crabs and should get out of there in no time.

    Noticing it was very busy at the fish counter, another staff person came over to help. I was ready to be served,  but the staff person went to the end of the line and began to help a couple of ladies with snails （蜗牛）.The customer in front of me, being served, turned around and looked at me sympathetically, and the customer behind me called to the staff person, "You should start her, "pointing at me. He was, well, ignored.

    If someone asked me, "What is the most important rule to follow in America？"I would reply without hesitation, "Wait your turn at all times." Wherever you go here in this country, you will find people waiting in a line quietly to get anything: whether in the supermarkets, department stores, bus stops, or gas stations, it's just a matter of waiting your turn. In a larger sense, "wait your turn" is more than just a guideline﹣it is a very basic norm （准则）that reflects the fundamental value of the western cultures. But in some situations your turn does not always come based on when you get there and how long you have waited in line, just like my case at the store. Even though this did not often happen, it did make me feel upset.

    Washington, D.C. Bicycle Tours

    Cherry Blossom Bike Tour in Washington, D.C.

    Duration: 3 hours

    This small group bike tour is a fantastic way to see a world-famous cherry trees with beautiful flowers of Washington, D.C. Your guide will provide a history lesson about the trees and the famous monuments where they blossom. Reserve your spot before availability—and the cherry blossoms—disappear!

    Washington Capital Monuments Bicycle Tour

    Duration: 3 hours (4 miles)

    Join a guided bike tour and view some of the most popular monuments in Washington, D.C. Explore the monuments and memorials on the National Mall as your guide shares unique facts and history at each stop. Guided tour includes bike, helmet, cookies and bottled water.

    Capital City Bike Tour In Washington, D.C.

    Duration: 3 hours

    Morning or afternoon, this bike tour is the perfect tour for D. C. newcomers and locals looking to experience Washington, D.C. in a healthy way with minimum effort. Knowledgeable guides will entertain you with the most interesting stories about Presidents, Congress, memorials, and parks. Comfortable bikes and a smooth tour route(路线) make cycling between the sites fun and relaxing.

    Washington Capital Sites at Night Bicycle Tour

    Duration: 3 hours(7miles)

    Join a small group bike tour for an evening of exploration in the heart of Washington, D.C. Get up close to the monuments and memorials as you bike the sites of Capitol Hill and the National Mall. Frequent stops are made for photo taking as your guide offers unique facts and history. Tour includes bike, helmet, and bottled water. All riders are equipped with reflective vests and safety lights.

Friends play an important part in our lives, and although we may take friendship for granted, we often don't clearly understand how to make friends. While we get on well with a number of people, we are usually friends with only a very few — for example, the average among students is about 6 per person. In all the cases of friendly relationships, two people like one another and enjoy being together, but beyond that, the degree of intimacy between them and the reasons for their shared interests vary greatly. As we get to know people, we take into account things like age, race, economic condition, social position, and intelligence. Although these factors are not of great importance, it is more difficult to get on with people when there is a marked difference in age and background.

Some friendly relationships can be kept on argument and discussion, but it is usual for close friends to have similar ideas and beliefs, the same opinions and interests — they often talk about "being on the same wavelength". It generally takes time to reach this point. And the more intimately involved people become, the more they depend on one another. People who want to be friends have to learn to put up with annoying habits and to stand differences.

In contrast with marriage, there are no friendship ceremonies to strengthen the association between two people. But the supporting and understanding of each other that results from shared experiences and emotions does seem to create a powerful bond, which can overcome differences in background, and break down barriers of age, class or race.