【The Invention of the Bicycle】
　　A French father-and-son team of carriage-makers,Pierre and Ernest Michaux,invented an improved bicycle in the 1860's.Many early bicycles (called velocipedes,meaning "fast foot," or,more descriptively,"bone shakers") had huge front wheels —— it was thought that the bigger the wheel,the faster you could go.Early tires were wooden —— metal tires were an improvement,and solid rubber tires were added later.A chain with sprockets was added to the bicycle in the 1880's; this was called the "safety bicycle." Air-filled tires were also added in the 1880's.The derailleur gear system was added in the 1970's.
　　Nowadays,it's important for us to live the low-carbon life.So riding bicycle is the best choice for us to go around.It's not only benefit for our health and also cheaper than cars and the oil is not necessary for bicycles.The better thing is,it was so friendly to environment that it won't produce any polution.So let's go for a ride!
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　　五星級回答,一定要采納哦,不要辜負我的辛苦勞動!
　　【來自英語牛人團】