Today we're going to discuss the history of the bicycle. The first bicycle, called the 'Draisine', was invented in 1817 by Karl von Drais. It had no pedals; riders pushed their feet against the ground to move. In the 1860s, pedals were added to the front wheel, creating the 'velocipede'. However, this was uncomfortable due to its solid rubber tires. The 'high wheeler' came next, with a large front wheel for speed, but it was dangerous. Finally, in 1885, the 'safety bicycle' was introduced, featuring two equal-sized wheels and a chain drive, making it much safer and more practical.
❓ 为什么“高轮自行车”被认为很危险？
A. A. 它没有刹车。
B. B. 它有一个大前轮，可能导致摔倒。
C. C. 它太重了，难以控制。
D. D. 它有实心橡胶轮胎。
✅ 正确答案
B. It had a large front wheel that could cause falls.