Recent years have witnessed the returning of bikes across China． An increasing number of people choose cycling instead of driving to school， to workplaces or to do sightseeing． Bike﹣sharing plans are warmly welcomed in many． cities． Mobike had 5.85million active users while Ofo had 1.4million in the first week of this year．

People can unlock the shared bikes by simply using their smartphones． All bikes have GPS and can be left anywhere in public for the next user． They're popular among many Chinese people

because they help solve "last﹣mile" problems in cities． For example， many people find it difficult to get to the hotel when they get off trains or to travel around the city．

However， the plans have also led to problems such as illegal（非法的） parking， vandalism （故意破坏） and theft． In February， two nurses in Beijing were placed under administrative detention（行政拘留） for five days for putting locks on two shared bikes．

In fact， these problems are also shared by bike﹣sharing plans abroad． Started in 2007， V6lib is the largest public bike sharing system in Paris． At its early period， it also met with problems of vandalism or theft． To deal with these problems， the company came up with the idea of encouraging people to return the bikes to stations by rewarding free time for their next rides．

Now， Chinese service Organizations are also trying to deal with these problems． For example， Mobike sets a 100﹣point credit score（信用分数） for each user， but the points will be taken because of his or her bad behavior． Once a score drops below 80， bike rental（租金） will be increased from 1yuan to 100yuan per 30minutes．

回答下面5个问题，每题答案不超过6个词

46．What do many people choose to go to school or work instead of driving？

　　

47．How do people unlock the shared bikes？

　　

48．Why are the shared bikes popular in cities？

　　

49．What reward will people get if they return V6lib bikes to stations？

　　

50．According to Mobike， how will a rider be punished if his or her credit score drops below 80？