Good morning. Today we're going to discuss the history of the bicycle. The first two-wheeled vehicle, called the Draisienne, was invented in 1817 by Karl von Drais. It had no pedals; riders pushed their feet against the ground. Then in the 1860s, pedals were added to the front wheel, creating the velocipede. However, it was extremely uncomfortable due to its rigid frame and iron wheels. The real breakthrough came in 1885 with John Kemp Starley's Rover Safety Bicycle, which featured a chain drive to the rear wheel and equal-sized wheels. This design made cycling much safer and more efficient, and it became the template for modern bicycles.
❓ Xe đạp an toàn Rover có lợi thế chính gì so với các mẫu xe trước đó?
A. A. Nó nhẹ hơn và dễ mang theo hơn.
B. B. Nó có bộ truyền động xích đến bánh sau và các bánh xe có kích thước bằng nhau.
C. C. Đây là chiếc xe đầu tiên có bàn đạp gắn vào bánh trước.
D. D. Nó sử dụng bánh xe sắt để có độ bền tốt hơn
✅ 正确答案
B. It had a chain drive to the rear wheel and equal-sized wheels