People can reduce air pollution by riding bicycles.

人们可以通过骑自行车来减少空气污染。

He hates some people riding bicycles on the sidewalk.

他恨有些人在人行道上骑自行车。

Children are prohibited from riding bicycles on the street.

禁止儿童们在街上骑车。

With the rapid development of economy, the number of people riding bicycles is decreasing .

随着经济的快速发展，骑自行车的人数是越来越少。

There are many kinds of vehicles, such as riding bicycles, driving cars. Which kind of vehicles do you like?

谈谈你对骑自行车与开小汽车两种交通方式的看法及你通常采用的方式。

In my hometown, there used to be a lot of people riding bicycles. But now most people choose to use public transportation or drive their own car.

在我的家乡，过去骑自行车的人很多。但是，现在大多数人选择使用公共交通工具，或驾驶自己的汽车。