用英文介绍一下自行车的发明

The history of human use of the wheel about 5000 years,and in 1839,Macmillan invented a mechanical bicycle.In 1861,a Frenchman named Brunel,the smaller front wheel,making cycling safer and the ongoing attempts to significantly.In 1885,the British Starley invented the bicycle chain drive.Created a large popular bike era.