Today we're going to discuss the history of the bicycle. The first two-wheeled vehicle, called the 'velocipede', appeared in the early 19th century. It had no pedals, so riders pushed their feet along the ground. In the 1870s, the 'penny-farthing' became popular, with a huge front wheel and a small rear wheel. However, it was dangerous because riders sat high above the ground. Then in 1885, the 'safety bicycle' was invented. It had two equal-sized wheels and a chain drive, making it much safer and more practical. By the early 20th century, bicycles had become a common mode of transport for ordinary people.
❓ 这款前轮大后轮小的自行车（Penny-farthing）的主要问题是什么？
A. A. 它太重了，无法骑上坡。
B. B. 它没有踏板，因此速度很慢。
C. C. 骑手们高高地坐在离地面很远的地方，因此十分危险。
D. D. 对大多数人来说太贵了。
✅ 正确答案
C. Riders sat high above the ground, so it was dangerous.