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In many countries in the process of industrialization, overcrowded cities present a major problem. Poor conditions in these cities, such as housing shortage, unemployment and inadequate sanitation, bring about an increase in the rate of poverty, disease and crime. The over-population of some cities and towns is mainly caused by the drift of large numbers of people from the rural areas.
在许多国家的工业化的过程中，城市过度拥挤出现重大问题。这些城市的欠缺条件，如住房短缺，失业和卫生设施不足等等，使得贫困加剧，疾病和犯罪上升。 导致一些城市和乡镇人口过多的主要原因是人们从贫困的农村的迁入城市。 翻译：薛荷莉（水平有限，仅供参考）