Recently, online hike-sharing has become the new favorite in China. In major cities, bikes in, yellow, orange, blue, white and green, can be seen almost everywhere on the street. It seems that these bikes appeared suddenly, adding a new beautiful scenery to Chinese cities.

    Both the market and the public welcome online bike-sharing, but is it really a promising business? Well, it depends. After all, online bike-sharing platforms can never get away with huge operating cost and uncertain government policy.

    Some theorists might say that online bike-sharing platforms can earn a fortune simply through deposit. Since users will always need to rent bikes, their deposit will always be kept to online bike-sharing platforms.

    However，although online bike-sharing platforms may be able to use the deposit for other purposes at the primary stage, they will have to set up a special account, so that the deposit shall be used specially for its designated (指定的) purpose. As the market gets increasingly mature, they will have to do so whether to be responsible for users or in consideration of possible government regulations.

    Now that online hike-sharing platforms can，t make profit through deposit，how can they become profitable as fiercer market unfolds? Although Hu Weiwei, CEO of Mobike, stated in an article that she would take Mobike as charitable(慈善的) project if she failed, running a startup is absolutely different from managing a charity organization. After all , she has to pay back investors' billions of investment(投资).

    To make profit, online bike-sharing platforms might have toincrease rent fee for each trip, just as Didi did

    From this aspect, it might be a really good business. If we consider full screen ads fee, recommendation fee for business owners, etc. , its annual income might reach at least RMB 15 billion. If we consider the huge operation cost, including bike repairs，bikes' service life and labor cost, there might not be much net profit left. After all, offline operation cost has always been an unbearable burden for such internet plus mode-based startups.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    When we see well, we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are.

    People who are near-sighted can only see things that are very close to their eyes. Everything else seems ­­blurry. Many people who do a lot of work, such as writing, reading and sewing become near-sighted. People who are far-sighted suffer from just the opposite problem. They can see things that are far away, but they have difficulty in reading a book unless they hold it at arm's length. If they want to do much reading, they must get glasses, too.

    Other people do not see clearly because their eyes are not exactly the right shape. They have what is called astigmatism (散光). This, too, can be corrected by glasses. Some people's eyes become cloudy because of cataracts (白内障). Long ago these people often became blind. Now, however, it is possible to operate on the cataracts and remove them.

    Having two good eyes is important for judging distances. Each eye sees things from a slightly different angle. To prove this to yourself, look at an object out of one eye; then look at the same object out of your other eye. You will find the object's relation to the background and other things around it has changed. The difference between these two different eye views helps us to judge how far away an object is. People who have only one eye cannot judge distances as people with two eyes.

                                                                        How to read more and learn more

    Today, more and more Chinese people enjoy sending and receiving messages on the phone. It can help them to get some information and communicate with friends. But I think I should read more books besides the textbooks, the more, the better. It can broaden（扩大）my mind and improve my language skills. {#blank#}1{#/blank#} Here are some tips for you.

    Clear your purpose for reading.

    {#blank#}2{#/blank#} Most people read for two main reasons, pleasure or knowledge. Clearing about your reading purpose can not only help you choose the books you really need to read, but also remind you why reading the book is important to you.

    {#blank#}3{#/blank#}

    No matter what you are reading, it is important to enjoy what you read. Although your friends like reading some kinds of books, those books might not be the ones you enjoy.

    Give up books that you don't enjoy.

    You may have chosen books that you are interested in, and they are right purpose. But while you are reading them, there may still be some books that you don't enjoy reading. Whenever you realize that you aren't enjoying the book you are reading, give it up. {#blank#}4{#/blank#}

    Set a reading goal.

    It is interesting that I read the books borrowed from libraries faster than than those I bought. The reason is the books I bought don't have a due date! I don't need to return those books. {#blank#}5{#/blank#} Before you read each book, ask yourself what time you need to complete this book by.

A. Read only what you are interested in.

B. Read the books borrowed from others.

C. Remember reading shouldn't be a chore (烦恼事).

D. Of course, it also can help me to get good grades.

E. We need to get the latest news and communicate with friends.

F. Before you start reading, ask yourself why you are reading this book.

G. Having a reading goal helps you work out how much reading you need to do in a week or even a day.

    The concept of “the body” is closely related to the ideas of “illness” and “health”. {#blank#}1{#/blank#} The main reasons for the differences are genetic, and the fact that people's bodies change as they age. However, a huge range of research indicates that there are social factors too.

    Poorer people are more likely to eat “unhealthy” foods, to smoke cigarettes and to be employed in repetitive, physically difficult work. {#blank#}2{#/blank#} That is to say, the physical shapes of bodies are strongly influenced by social factors.

    These social factors are also closely linked to emotional wellbeing. People with low or no incomes are more likely to have mental health problems. {#blank#}3{#/blank#} For example, certain people with mental health issues may be at risk of becoming homeless, just as a person who is homeless may have an increased risk of illnesses such as depression.

    {#blank#}4{#/blank#} Bodies are young or old, short or tall, big or small, weak or strong. Whether these judgements matter and whether they are positive or negative depends on the cultural and historical contexts. The culture, and media, of different societies promote very different valuations of body shapes. {#blank#}5{#/blank#} Currently, in rich societies the idea of slimness is highly valued, but historically this was different. It is easy for people to feel undervalued because of factors they have no power to change, for example, their age and height. Equally, they can feel pressured into making changes to their appearance when there is a choice, which in some cases can lead to an unhealthy interest in weight loss. Therefore, sociologists are suggesting that we should not just view bodies and minds in biological terms, but also in social terms.

A. There are other types of social factors too.

B. All of these factors affect the condition of a person's health.

C. Their housing conditions and neighbourhoods need to be improved.

D. What is considered as attractive or ugly, normal or abnormal varies greatly.

E. All of us exist in “bodies” of different shapes, heights, colours and physical abilities.

F. Social factors in general play an important role in the development of people's body conditions.

G. It is not clear, however, whether the situation of being poor causes mental illness, or whether it is the other way around.

    Fashions have a lot of rules. Most of them, however, are just wrong. But there's one rule that goes beyond tradition and into the field of scientific study of the brain: Black clothes are slimming. It all comes down to how your visual system processes the light. The below holes in each square are the same in size, yet the white hole looks bigger than the black hole.

    In the 1500s, Galileo Galilei noticed that some of the planets looked larger when viewed with the naked eye than they did when viewed through a telescope, making the white light of Venus appear eight to ten times larger than Jupiter in the night sky. He knew something strange must be going on with his vision to cause this illusion, but he wasn't sure what it was. Luckily, scientists never stopped wondering, and in 2014, they figured it out.

    Our visual system operates via two main channels: "on" neurons (神经元) that are sensitive to light things and "off" neurons that are sensitive to dark things. When it came to the dark "off" neurons, the researchers found that they responded predictably to dark shapes on a light background the greater the contrast between the two, the more active these neurons were. But the light on" neurons behaved unpredictably. Even with the same amount of contrast, light objects on a dark background caused a greater response in these neurons.

    This phenomenon makes some sense, evolutionarily speaking. In the dark of night, you'd want to be able to take in every bit of light you can get, so a visual system that enlarges light objects on a dark background could be very useful. However, it's not that hard to see dark objects in the light of day. It has some effects in the colors of your clothes and in the appearance of the planets—the brighter appearance of Venus in the night sky makes it look bigger than the darker Jupiter.

Beijing Opera represents the finest combination of literature, music, dance, kung fu, fine arts and many other arts. Its way of performing is different from opera and drama. {#blank#}1{#/blank#}

Beijing Opera is a kind of art that pays equal attention to singing，speaking，acting and fighting. {#blank#}2{#/blank#} Meanwhile, Beijing Opera provides the opportunity to appreciate the pleasing artistic balance of the dance, the strength and music, even from only one act. {#blank#}3{#/blank#} According to the historical record, it dates back to the middle period of the Qing Dynasty. In the 55th year ruled by the Emperor Qianlong, the most famous four theatrical groups in Anhui went to Beijing to show their opera performance and then got a great success. Then, based on "Anhui Opera" and "Han Opera", and also mixed with characteristics of Beijing dialect, Beijing Opera was formed. {#blank#}4{#/blank#}

The Beijing Opera was officially formed after the 20th year of the Emperor Daoguang (1840). At that time, the forms of each kind of arias (唱腔) and the language characteristic of Beijing Opera originally came into being. New changes appeared in Beijing Opera's roles. {#blank#}5{#/blank#} Later, the first generation of the opera actors also appeared.

A. Beijing Opera is a kind of modem opera.

B. Actually Beijing Opera has its own characters.

C. Many roles of the Beijing Opera had appeared.

D. Because it was popular in Beijing, it spread nationwide.

E. Many people wonder what is the origin of the Beijing Opera.

F. It enables the audience to be inspired by language, music and fine arts.

G. Although in was formed in Beijing it didn't have its origins in Beijing totally.