Instruction:
What is bicycling and why would someone do it?  Is bicycling healthy and joyful or is it painful and a waste of time?  How many bicycles should you have?  Which part of the world do you find the most people bicycling?

Response:
Bicycling is a form of human powered movement that typically involves sitting or standing on a machine with two wheels that can be propelled forward by using one's arms or legs.  The bicycle was invented in the early 1800 (1817) by a German inventor named Drais.  The early bicycles were built from wood and soon after used heavy steel for the frame and wheels.  These steel bikes were called Boneshakers because when you road on them you would feel every stone and bump through your bones.  Bicycling exists in nearly every corner of the world, on every continent and it is done by all people.  In many countries, bicycling is the primary mode of transportation for people, especially in urban settings.  Bicycling is also a professional sporting competition where men and women race against one another in large groups in front of cheering crowds.  Bicycling is a very efficient form of converting power generated by a human into forward motion.  While most humans can't run faster than 10 miles per hour for more than a few miles, humans can go much faster and often hundreds of miles when using a bicycle.  Because modern bicycles use pneumatic tires and have many gears, it is considered a very healthy form of exercise.  People who love bicycling often have many different bicycles for different conditions, such as dirt or gravel, pavement, snow and even sand.