Good morning, everyone. Today we'll discuss the history of the bicycle. The first two-wheeled vehicle, called the draisine, was invented in 1817 by Karl Drais. It had no pedals; riders pushed their feet against the ground. Later, in the 1860s, pedals were added to the front wheel, creating the velocipede. However, it was nicknamed the 'boneshaker' because of its rigid frame and rough ride. By the 1880s, the safety bicycle appeared with a chain drive and equal-sized wheels, making it much more stable and popular among both men and women. This design became the basis for modern bicycles.
❓ What was the main improvement of the safety bicycle compared to earlier models?
A. A. It had a front wheel with pedals.
B. B. It used a chain drive and equal-sized wheels, making it more stable.
C. C. It was lighter and cheaper to produce.
D. D. It had rubber tires for a smoother ride.
✅ 正确答案
B. It used a chain drive and equal-sized wheels, making it more stable.