请英文好的朋友帮助修正一下英语作文,主题关于“城市化”

请英文好的朋友帮助修正一下英语作文,主题关于“城市化”
Nowadays,with rapid urbanization,experts predict that,50% of people live in cities 70% by 2050.
Though there are many slum which even can't provide a good health environment such as drinking water and sanitation,but still,the size of urbanisation in developing countries are unprecedented.
Compare the town,the Infrastructure and services are quite good in urban which caused a huge migration from rural to city.A lot a significant percentage of the population will be migrating from rural areas to urban to seek better job opportunity and living standards.A lot of cities become megacities which the proportion more than 10 million while the population soars such as London,Shanghai,Tokyo.
According to statistics,10% of world’s population live in megacities.This causes serious issues such as traffic jam,environmental pollution.
So,megacity is one of the major issues of 21st century.