Good morning. Today we're going to 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. It was called a 'hobby horse'. Later, 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, making cycling much safer and more efficient. This design is essentially the basis for modern bicycles.
❓ Điều gì đã làm cho 'xe đạp an toàn' trở nên phổ biến vào những năm 1880?
A. A. Nó có một chỗ ngồi thoải mái
B. B. Nó có bộ truyền động xích và các bánh xe có kích thước bằng nhau.