Biking is a popular form of exercise because it's healthy and environmentally friendly.
Many cities have made efforts to make cycling (easy) and more popular. In the US, Bike to Work Day (hold) on May 20th every year. The aim of the day is to encourage more people (ride) bikes.
Copenhagen, the capital Denmark, is the world's most bike-friendly city. During rush hour, traffic-lights are always green for bikes. When it's snowy, people clear the snow in bicycle lanes (one), and the car lanes come next.
In Amsterdam, people can rent bike almost anywhere in the city. You can always find bike rental companies near busy (area).
In China, we have bike-sharing companies. They make more convenient for people to use bikes. However, biking is not that easy in many Chinese cities. Cars often take up Bicycle lanes and(bike) have to ride next to cars in car lanes. It is very dangerous. Chinese government is doing it can to improve the situation.
