Good morning, everyone. 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 'penny-farthing'. However, this design was dangerous because riders sat high above the ground. It wasn't until the 1880s that the 'safety bicycle' with two equal-sized wheels and a chain drive was introduced, making cycling much safer and more popular.
❓ Theo bài giảng, vấn đề chính của xe đạp 'penny-farthing' là gì?
A. A. Nó không có bàn đạp.
B. B. Nó quá nặng để đi.
C. C. Người lái ngồi quá cao và có thể dễ dàng ngã.