帮忙把下面这段中文翻译成英文 万分感谢！！

the densely populated city in Asia is fast to carry out the retrofit of old residential area on a largescale.Most of these old residential area safety evacuation planning lag,population and building density,building is old,evacuation channel not free public safety hidden trouble.How to make the early warning in disaster evacuation weak area of the old residential area, optimization of evacuation route eventually complete massive crowd evacuation,reduce disaster has become the problems of China have to save on planning and construction and old district in the process of updating!