1. Around the world , there are many city which are facing overcrowding
2. Saigon is the most populous city in Vietnam with the population of 8.6 million
3. In overpopulated cities, public transport is usually overcrowded especially during rush hour
4. Large numbers of people have moved from the countryside to the cities in recent years
5. There are more job opportunities in the big cities than in the rural area , aren't there ?
6. Local goverments have to find a solution for housing shortage
7. A Lot pf peple who are homeless are suffuring from health problems
8. Over the next ten years , the population of the world will have grown by 1 billion
