Good morning, class. Today we're going to discuss the history of the bicycle. The first two-wheeled vehicle, called a draisine, was invented in Germany in 1817. It had no pedals; riders pushed their feet against the ground to move. Later, in the 1860s, pedals were added to the front wheel in France. However, these early bicycles were uncomfortable because of their solid rubber tires. It wasn't until 1888 that John Boyd Dunlop invented the pneumatic tire, which made riding much smoother. This innovation greatly increased the popularity of cycling.
❓ 1888年之前，自行车的主要问题是什么？
A. A. 它们太重了，没法骑。
B. B. 它们的实心轮胎使乘坐体验很不舒适。
C. C. 它们仅在法国和德国有售。
D. D. 直到1888年，它们才装有踏板。
✅ 正确答案
B. They had solid tires that made rides uncomfortable.