Shanghai is one of the first cities in China to see bike sharing fever. Shared bikes can now be found all over the city. On streets see riders of your age. Some might even be younger than you. Unluckily, there have been some accidents involving (涉及) shared bikes.

    One of the most serious accidents took place in March. One Sunday afternoon, a boy was riding an ofo bike (共享单车). He was hit by a bus and later died. The boy's parents were not by his side. He was only about 10 years old.

    The good news is that Shanghai has been trying to manage bike sharing by making rules. The rules are still being discussed, but some of the rules have been decided on. Users must be between 1. 45 and 1.95 meters tall.

    However, it could be hard to make these rules work. Ou Jing is ofo's manager in Shanghai. He said the company had banned (禁止) children under 12 from using its service. Yet, young children can still be seen riding ofo bikes. That's because many ofo bikes use manual (手动的) locks. Ofo has developed electronic locks. However, it will take some time for the company to fix the new locks on all of its bikes.

    Most of you are old enough to ride a shared bike. Still, please ride slowly for your own safety. When you finish using the bike, don't forget to park and lock it properly—for everybody's safety.

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