Good morning, everyone. Today we're going to discuss the history of the bicycle. Now, most people think the bicycle was invented in the 19th century, but its origins actually go back further. The first two-wheeled vehicle, called a draisine, was created by a German baron, Karl von Drais, in 1817. It had no pedals; riders pushed their feet against the ground. Later, in the 1860s, pedals were added to the front wheel in France, leading to the 'boneshaker'. However, the major breakthrough came in 1885 when John Kemp Starley introduced the 'Rover' safety bicycle, which had a chain-driven rear wheel and equal-sized wheels, making it much safer and more practical. This design became the basis for modern bicycles.
❓ 강의에 따르면, 로버 안전 자전거의 주요 혁신은 무엇이었나요?
A. A. 페달이 달린 최초의 자전거였다.
B. B. 체인을 사용하여 뒷바퀴를 구동했으며, 같은 크기의 바퀴를 갖추고 있었다.
C. C. 그것은 전적으로 나무로 만들어졌으며 금속 부품이 전혀 없었다.
D. D. 그것은 1817년에 발명된 최초의 이륜 차량이었다.
✅ 正确答案
B. It used a chain to drive the rear wheel and had equal-sized wheels.