第6部分：完形填空(第51—65题，每题1分，共15分)
　　下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。

The First Bicycle

　　The history of the bicycle goes back more than 200 years. In 1791, Count de Sivrac (51) onlookers in a park in Pads as he showed off his two-wheeled invention, a machine called the celerifere. It was basically an (52) version of a children's toy which had been in (53) for many years. Sivrac's "celerifere" had a wooden frame, made in the (54) of a horse, which was mounted on a wheel at either end. To ride it, you sat on a small seat, just like a modem bicycle, and pushed (55) against the (56) with your legs —there were no pedals. It was impossible to steer a celerifere and it had no brakes, but despite these problems the invention very much (57) to the fashionable young men of Paris. Soon they were (58) races up and down the streets.
　　Minor (59) were common as riders attempted a final burst of (60) Controlling the machine was difficult, as the only way to change (61) was to pull up the front of the "celeriferes" and (62) it round while the front wheel was (63) in the air. The "celeriferes" were not popular for long, however, as the (64) of no springs, no steering and rough roads made riding them very uncomfortable. Even so, the wooden celerifere was the (65) of the modem bicycle.
　　51. A. delighted.
　　B. cheered
　　C. appreciated
　　D. overjoyed
　　52. A. increased
　　B. enormous
　　C. extended
　　D. enlarged
　　53. A. use
　　B. play
　　C. operation
　　D. service
　　54. A. resemblance
　　B. shape
　　C. body
　　D. appearance
　　55. A. fast
　　B. deeply
　　C. heavily
　　D. hard
　　56. A. surface
　　B. ground
　　C. earth
　　D. floor
　　57. A. attracted
　　B. appealed
　　C. took
　　D. called
　　58. A. going
　　B. getting
　　C. holding
　　D. making
　　59. A. wounds
　　B. trips
　　C. injuries
　　D. breaks
　　60. A. velocity
　　B. energy
　　C. pace
　　D. speed
　　61. A. direction
　　B. route
　　C. heading
　　D. way
　　62. A. roll
　　B. drive
　　C. turn
　　D. revolve
　　63. A. cycling
　　B. circling
　　C. winding
　　D. spinning
　　64. A. mixture
　　B. link
　　C. combination
　　D. union
　　65. A. origin
　　B. design
　　C. model
　　D. introduction