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    About 30 years ago, China was known as the "Bicycle Kingdom". But the two-wheeled mode（方式） of transport's popularity began to disappear Many bikes were soon replaced by their fuel-powered competitors. But recent months, we have seen a revival of bikes across China. An increasing number of people choose cycling instead of driving to schools, to workplaces or to do sightseeing. The introduction of bike-sharing project, which was firstly started by newly set up companies like Ofo and Mobike, has brought the popularity to a new level.

    According to the data, the first week of this year saw 5.85 million active users of Mobike while Ofo had 1.4 million active users. People can unlock the shared bikes by simply using their smart phones. The bikes are equipped with GPS and can be left anywhere in public for the next user. They're popular among many Chinese people because they provide an effective solution to the "last mile" problem, which people have to walk to their destinations in the last part of their journeys.

    "In places where the subway doesn't arrive, where it's difficult to change from one kind of transport to another, it's so easy to get where you want to go with Mobike;”Hu Hong 29, told AFP. She rides to his workplace every day.

    However, the  project has also led to problems such as illegal parking, vandalism (故意破坏 ) and theft. Last month, two nurses in Beijing were placed under administrative detention（行拘留）for five days for putting locks on two shared bikes. And in December, a man who stole a shared bike was sentenced to a 3-month detention and fined 1, 000 yuan by the Shanghai Minhang People's Court.

    In fact, to deal with these problems, some foreign companies came up with the idea of encouraging people to return the bikes to stations by giving them free time for their next rides as a pride. Now, Chinese service operators are also trying to solve these problems. For example, Mobike sets a100-point credit(信用） score for each user. The points will be taken if there is bad behavior. Once a score drops below 80, bike rental is increased t0 100 yuan per 30 minutes. up from 0.5-1 yuan.