Good morning, everyone. Today we're going to discuss the history of the bicycle. One key figure is Karl von Drais, who invented the 'running machine' in 1817. This early bicycle had no pedals; riders pushed their feet against the ground. Later, in the 1860s, pedals were added to the front wheel, creating the 'boneshaker'. However, it was not until the 1880s that the 'safety bicycle' with a chain drive and two equal-sized wheels became popular, making cycling much safer and more accessible to the general public.
❓ 19世纪80年代推出的“安全自行车”的主要特点是什么？
A. A. 它有一个大前轮，没有踏板。
B. B. 它采用了链传动和两个大小相同的轮子。
C. C. 它由一个小的马达驱动。
D. D. 它要求骑手用脚蹬地前行。
✅ 正确答案
B. It used a chain drive and two equal-sized wheels.