参考范文：
As is clearly illustrated in the above column， population both in cities and villages has experienced significant changes. While there was a dramatic decrease in the number of rural population from 1990 to 2010， the number of urban population significantly increases from300 million in 1990 to more than 650 million in 2010.
So why does this phenomenon appear？ From my perspective， it mainly results from two- fold factors. On one hand， with the background of highly developed economy in cities， urban areas need larger workforce to meet the requirements of development and construction in cities. And accordingly the advancement of industry and commerce in cities attract more and more rural laboring forces. On the other hand， the turning of people‘s attitude toward life should be responsible for the phenomenon epitomized in the diagram above， so a number of residents in cities move to countryside in order to enjoy the rural life.
As the society further develops， the trend in the chart is bound to continue for years in the forthcoming future. While we taste the fruits of urban development， we are supposed to be on guard against unfavorable effects of urbanization. （224 words）