Today we're going to discuss the history of the bicycle. The first two-wheeled vehicle, called the draisine, was invented in 1817 by a German baron. 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 design was uncomfortable due to its rigid frame. It wasn't until the 1880s that the safety bicycle, with a chain drive and two equal-sized wheels, became popular. This design greatly improved stability and safety, leading to the bicycle boom of the 1890s.
❓ Xe đạp an toàn đã có cải tiến lớn nào so với các thiết kế trước đó?
A. A) Nó có chỗ ngồi thoải mái hơn.
B. B) Nó sử dụng bộ truyền động xích và các bánh xe có kích thước bằng nhau.