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Bicycle sharing systems are also known as yellow bicycle programs, white bicycle programs, publicbikes or free bikes. They are increasingly popular in Europe now. Paris has the world's largest urban cyclerental system.

This is a bike rental station in Paris. The workers are showing how to use a new self-service bike. Theysay that Paris will become "a green eapitat of bikes" and they plan to park 20,000 bicycles at 1,600 sta-tions. Paris created this plan to reduce waste gas displacement( 废弃排放量).

At a rental station, you only have to put your credit card into the machine to rent a bike. It providesFrench, German, English and Chinese services. If you ride the bike for only 30 minutes to relax, youneedn't pay for it. A two-hour bike rent only costs you 4 Euros.

These stations work for 24 hours every day, so a bike is rented for 10 to 14 times a day. In this waythere are 200,000 people using bikes a day.

In the past few years, Paris has encouraged its people to ride bikes, but something unhappy has hap-pened now and then. Some people break the traffic rules during rush hours. Some park their bikes every-where. So how to park their bikes is a problem that Pairs will face, but this project is still a helpful way toimprove its traffic environment.

Why did Paris build many rental systems?

How many languages does the machine at a bicycle rental system offer?

According to the passage, the problem that Paris will deal with is how to__________.