5. If you wanna take a ride, just download the app and scan the QR code. Unlocking the smart lock means you have started the timer. 　　如果你想骑单车，只要下载应用，扫描二维码就行。解开智能锁意味着计时器已开启。 　　作文展开思路 第一段：可以客观叙述共享单车现状： Bike-sharing services took off in Chinese cities in the past two years. They allows riders to hire bikes for about one yuan per hour via a mobile app, and drop them off for the next user. 　　Customers are able to pick a bike anywhere in the city (thanks to the GPS-enabled app) and leave it anywhere at the end of their journey. 　　Users can rent a bike at a low cost, usually around 1 yuan an hour,depending on the brand. The services mostly target short-distance travel, such as between a subway station and work, or from home to the grocery store. They usually require a deposit for registration. 第二段：分点阐述共享单车的优缺点 1. 优点： 　　Bike sharing plays a positive role in many ways-meeting publicneeds, solving the "last mile problem" in urban public transport and easing urban traffic. 　　高分过渡版： 　　The service has reduced traffic congestion and cut auto emissions, but haphazardly parked bikes often block sidewalks, causing complaints. 　　2. 缺点： 　　Bike sharing has brought new problems to the city management, such as illegal parking and entering and exiting private areas without approval. 　　Shared bikes are easily accessible to children as a result of its technical defects. It is reported that some accidents happened to children when they were riding shared bikes. 　　The shared bikes are often parked at random and often block sidewalks. 第三段：总结你的看法 Rules should be released to regulate the use and park of sharing bikes. 　　For example, forbid children under the age of 12 from riding shared bikes, or ban the shared bikes enter private areas, and so on. 　　The bike sharing companies should be responsible for the park of the bikes. High technology can be used to help the bikes to be parked in the specified locations. （编辑：何莹莹）