One of the most popular and enduring myths about depression is that depressed people are sad all the time—and that by extension, people who are happy can't be experiencing depression, even if they say they are. It is a mistaken version of depression. Depression doesn't make you sad all the time.

    When I'm having a depressive feeling, I'm not walking around in black clothes, and weeping. I go out with friends. I play jokes. I keep working, and have friendly chats with the people I work with. I read books. Above all, I experience moments of happiness. Yet I feel a strange conflicting pressure. On the one hand, I feel like I need to engage in a sort of sadness for people to understand that I really am depressed and that each day is a struggle for me. Because that way I will appear suitably sad, and thus, depressed—and then maybe people will recognize that I'm depressed and perhaps they'll even offer support and assistance.

    On the other hand, I feel an extreme pressure to perform just the opposite, because sad depressed people are boring and no fun, as I am continually reminded every time I speak openly about depression or express feelings of sadness and frustration. I'm caught in a trap where if I don't perform sadness, I'm not really depressed, but if I express sadness at all to any degree, I'm annoying and boring and should stop being so self-centered. Depression can become your master, but you can slip out from under it occasionally. And many depressed people don't actually spend it fainting dramatically on the couch and talking about how miserable they are.

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    Thousands of persons in Peru are suffering from the disease cholera. Medical experts say it is the first time in their century that cholera has reached the western part of the world. The Untied States Centers for disease Control says the kind of cholera has been spreading throughout the world since 1961. It was discovered that year in Indonesia. Since the first case in Peru, more than sixteen thousand people have been affected and about one hundred have died.

    Cholera is caused by polluted food and water. People become infected (传染 ) when they eat the polluted food or drink the polluted water. If untreated immediately, they may die within hours. Most victims however , can be saved. treatment includes drugs and replacement of body fluids ( 液体) directly into the blood.

    Medical researchers have developed a vaccine ( 菌苗) medicines to protect against cholera. But the vaccine is only about 50% effective. And it protects against cholera for only about six months. Medical experts say the best way to fight cholera is to prevent it. They also say people should not eat uncooked food or food that has not been cooked long enough. People who live in areas where cholera has been found should wash their hands before eating and cooking. They should drink only water that has been boiled or made pure with chemicals.

    A Hobby is a regular activity that is done for enjoyment, typically during one's leisure（闲暇的） time. By continually taking part in a particular hobby, one can acquire practical skill and knowledge in that area. Is travel a good hobby? Travel, in the youngest sort, is a part of education and, in the elder, a part of experience. Some may think otherwise. To them, visiting churches, castles, libraries, etc. is an absolute wastage of time. They may further say that one can read the account of these or see the films of the important places of the world. They forget that touch of actuality gives a different type of sensation and satisfaction.

    Travelling may be an expensive hobby but it makes up for the financial loss. If a traveller has interest in life and its manifestations（表现）, one can find much to keep oneself absorbed and happy. A student of any stream can definitely find something of his own interest and studies. One can definitely find everything that satisfies his cravings for knowledge and feelings.

    As a hobby, travelling keeps us busy during leisure time; it is the best method to make use of time. Till a person breaks from dull routine, physically and mentally, one cannot find satisfaction. Travelling helps us to achieve this break. At a new place, one is curious to know and eager to gather all the unknown information about the place which he has neither read nor heard before and he gets thrills and surprises which keep the interest and enthusiasm alive and encourage us to keep our journey on.

    While travelling, one comes across a number of people from varied backgrounds and places. By interacting with them, he comes to know about their traditions also. In case one has psychological bent of mind, one increases one's experience and power to understand others. Understanding human nature is, perhaps, the best part of education. Travelling satisfies all demands of a good hobby-it is absorbing education and refreshment to the mind, body and soul.

    I was never very neat，while my roommate Kate was extremely organized. Each of her objects had its place，but mine always hid somewhere. She even labeled(贴标签) everything. I always looked for everything. Over time，Kate got neater and I got messier. She would push my dirty clothing over，and I would lay my books on her tidy desk. We both got tired of each other.

    War broke out one evening. Kate came into the room. Soon，I heard her screaming，“Take your shoes away！Why under my bed！” Deafened，I saw my shoes flying at me. I jumped to my feet and started yelling. She yelled back louder.

    The room was filled with anger. We could not have stayed together for a single minute but for a phone call. Kate answered it. From her end of the conversation，I could tell right away her grandma was seriously ill. When she hung up，she quickly crawled(爬) under her covers，sobbing. Obviously，that was something she should not go through alone. All of a sudden，a warm feeling of sympathy rose up in my heart.

    Slowly，I collected the pencils，took back the books，made my bed，cleaned the socks and swept the floor，even on her side. I got so into my work that I even didn't notice Kate had sat up. She was watching，her tears dried and her expression one of disbelief. Then，she reached out her hands to grasp mine. I looked up into her eyes. She smiled at me，“Thanks.”

    Kate and I stayed roommates for the rest of the year. We didn't always agree，but we learned the key to living together：giving in，cleaning up and holding on.

    The BeiDou Navigation Satellite System（BDS）is a Chinese satellite navigation system. It consists of two separate satellite constellations（星座）. The first BeiDou system, officially called the BeiDou Satellite Navigation Experimental System and also known as BeiDou-1, consists of three satellites, which since 2000 has offered limited coverage and navigation services, mainly for users in China and neighboring regions. Beidou-1 was decommissioned at the end of 2012.

    The second generation of the system, known as COMPASS or BeiDou-2, became operational in China in December 2011 with a partial constellation of 10 satellites in orbit. Since December 2012, it has been offering services to customers in the Asia-Pacific region.

    In 2015, China started the build-up of the third generation BeiDou system（BeiDou-3）in the global coverage constellation. The first BDS-3 satellite was launched on 30 March 2015. Up to January 2018, nine BeiDou-3 satellites have been launched. BeiDou-3 will eventually consist of 35 satellites and is expected to provide global services upon completion in 2020. So far, China has sent 27 BeiDou satellites into space. When fully completed, BeiDou, the world's fourth navigation satellite system, following GPS in the United States, GLONASS in Russia and Galileo in the European Union, will provide an alternative global navigation satellite system to the United States owned Global Positioning System（GPS）, and is expected to be more accurate than the GPS. It was claimed in 2016 that BeiDou-3 will reach millimeter-level accuracy（with post-processing）, which is ten times more accurate than the finest level of GPS.

    According to China Daily, in 2015, fifteen years after the satellite system was launched, it was generating a turnover of $31.5 billion annually for major companies such as China Aerospace Science and Industry Corp, AutoNavi Holdings Ltd, and China North Industries Group Corp.

    Polish President Andrzej Duda has signed a bill into law that largely limits trade on Sundays, saying it will benefit family life.

    The legislation（立法）, worked out by the government and the Polish trade union, is expected to draw protests from large western supermarket chains that are the main target of the law. A large part of their profit is earned on weekends.

    As of March 1, shops and markets are closed on two Sundays per month; in 2019 only one Sunday a month will be open for shopping; and starting in 2020, there will be no Sunday shopping with a few exceptions.

    Duda praised the law as giving children a chance to be with parents and giving shop workers some needed time off. He also said big traders will need to adjust their practices to the new system and asked them for "understanding". But critics say some of them make employees work long hours for modest pay.

    "A family should be together on Sundays," Olszewska said after buying some food at a local Biedronka, a large discount supermarket chain. She said that before she retired she served cold cuts in a grocery store, and was grateful she never had to work on Sundays.

    There are some exceptions to the ban. For instance, gas stations, cafes, pharmacies and some other businesses are allowed to keep operating on Sundays.

    Anyone breaking the new rules faces a fine of up to 100,000 zlotys （$ 29,500）, while repeat offenders may face a prison sentence. Polish trade union appealed to people to report any violators to the National Labor Inspectorate, a state body.