In today's lecture, we'll discuss the history of the bicycle. The first bicycle, invented in the early 19th century, had no pedals; riders pushed their feet against the ground. Later, the penny-farthing, with a large front wheel, became popular but was dangerous. In 1885, the safety bicycle was introduced, featuring two equal-sized wheels and a chain drive, making it much safer and more practical. This design quickly replaced earlier models and laid the foundation for modern bicycles.
❓ Sự cải tiến quan trọng nào của xe đạp an toàn so với các mẫu xe trước đó?
A. Nó có bánh trước lớn hơn để đạt tốc độ cao.
B. Nó sử dụng bộ truyền động xích và các bánh xe có kích thước bằng nhau.