They go to the park by bike

骑车───cycling

Cycling along the motorway is not allowed.───在快车道上骑车不行.

Cycling is good exercise. It strengthens all the muscles of the body.───骑自行车是一项不错的锻炼方式。它能使身体各部分的肌肉更强健。

Cycling is Europe's second most popular sport.───骑自行车是欧洲第二流行的体育运动。

the increasing popularity of cycling───骑自行车运动的日益风行

They now face the prospect of having to wear a cycling helmet by law.───他们现在面临的情形是：不久将需要依法佩戴摩托车头盔。

This text summarizes the status of and advances in nitrogen biogeochemical cycling and the possible problems.───文章全面综述了氮素生物地球化学过程研究的现状与进展及其可能存在的问题.

You might want to consider cycling.───你或许可以考虑骑自行车。

Cycling is a cheap way to get around.───骑自行车是一种省钱的旅游方式。

This plan which also includes Cycling Around the world, countries and continents climbing the peak.───这个计划其中还包括骑自行车环游世界, 攀登各个国家及各大洲的最高峰.

Recently I've started to do a lot of walking and cycling.───最近我开始经常散步和骑自行车。