请英文好的朋友帮助修改一下英文小短文.

请英文好的朋友帮助修改一下英文小短文.
Nowadays,with rapid urbanization,expertspredict that 50% of people live in cities.It is predicted that the statisticwill increase to 70% by 2050.
Although there are many slum areas whichcan't even provide a healthy environment with facilities like drinking waterand sanitation,the size of urbanisation in developing countries areunprecedented.
Compared to rural areas,the infrastructureand services are quite good in urban areas,which has caused a significantpercentage of the population migrated from rural areas to urban areas to seekbetter job opportunity and living standards.A lot of cities have becomemegacities with the proportion of more than 10 million.The most significantpopulation soars are London,Shanghai,Tokyo and such.
According to statistics,10% of world’spopulation live in megacities.This has caused serious issues such as trafficjam and environmental pollution.
In conclusion,megacities are one of themajor issues of the 21st century.