Good morning, everyone. Today we're going to look at the history of the bicycle. Now, you might think the bicycle is a fairly modern invention, but in fact, the first two-wheeled vehicle, called the draisine, was invented in Germany in 1817. It had no pedals, so riders pushed their feet against the ground to move. Later, in the 1860s, pedals were added to the front wheel in France, which made riding faster but also more dangerous. It wasn't until the 1880s that the chain drive was introduced, allowing the rear wheel to be powered, which is the design we still use today. So, to summarize, the key change that made bicycles safer and more practical was the addition of the chain drive.
❓ 강사는 1880년대에 도입된 체인 드라이브의 주요 장점이 무엇이라고 말했습니까?
A. A. 그것은 자전거를 이전보다 더 빠르게 만들었다.
B. B. 그것은 기수가 안전하게 뒷바퀴에 동력을 전달할 수 있게 해주었다.
C. C. 페달의 필요성을 완전히 없앴다.
D. D. 그것은 자전거를 더 가볍고 운반하기 쉽게 만들었다.
✅ 正确答案
B. It allowed the rider to power the rear wheel safely.