试题题干
With the development of industry and extension of railroad network in the early 20th century in the U.S.A., there appeared （）.
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正确答案：
试题解析
随着20世纪初美国的工业发展和铁路网络的扩展，城市出现了快速增长。
With the development of industry and extension of railroad network in the early 20th century in the U.S.A., there appeared （）.
随着20世纪初美国的工业发展和铁路网络的扩展，城市出现了快速增长。