Nowadays, with rapid urbanization, experts predict that 50% of people live in cities. It is predicted that the statistic will increase to 70% by 2050.
Although there are many slum areas which can't even provide a healthy environment with facilities like drinking water and sanitation, the size of urbanisation in developing countries are unprecedented.
Compared to rural areas, the infrastructure and services are quite good in urban areas, which has caused a huge migration from rural areas to urban areas in the past few years. A significant percentage of the population migrated from rural areas to urban areas to seek better job opportunity and living standards. A lot of cities have become megacities with the proportion of more than 10 million. The most significant population soars are London, Shanghai, Tokyo and such.
According to statistics, 10% of world’s population live in megacities. This has caused serious issues such as traffic jam and environmental pollution.
In conclusion, megacities are one of the major issues of the 21st century.
基本上没有什么错误,但我改了一些病句,也加了一些优美的词句.采纳吧.