In today's lecture, we'll discuss the history of the bicycle. The first bicycle, invented in the early 19th century, had no pedals and was pushed along by the rider's feet. Later, in the 1860s, pedals were added to the front wheel, making it faster but more dangerous. By the 1880s, the 'safety bicycle' with two equal-sized wheels and a chain drive became popular, as it was much safer and easier to ride. Interestingly, this design is essentially what we still use today. However, the introduction of pneumatic tyres in the 1890s greatly improved comfort and speed, which led to a cycling boom.
❓ 是什么让“安全自行车”比早期设计更受欢迎?
A. A. 它的前轮上装有踏板。
B. B. 它有两个大小相同的轮子和一个链条传动装置。
C. C. 这是有史以来发明的第一辆自行车。
D. D. 它更快但更危险。
✅ 正确答案
B. It had two equal-sized wheels and a chain drive.