Today we're going to discuss the history of the bicycle. One common misconception is that the bicycle was invented in the 19th century, but in fact, early prototypes appeared much earlier. For example, a drawing from 1493 by Leonardo da Vinci shows a basic two-wheeled vehicle. However, the first practical bicycle, called the 'Draisine' or 'running machine', was created by Karl Drais in 1817. It had no pedals; riders pushed their feet against the ground. The key improvement came in 1860s when pedals were added to the front wheel, but this made the bicycle unstable. Finally, in 1885, the 'safety bicycle' with a chain drive and equal-sized wheels was introduced, which became the model for modern bikes.
❓ Согласно лекции, в чём заключалась основная проблема ранних велосипедов с педалями на переднем колесе?
A. Они были слишком тяжёлыми, чтобы ездить на них.