In the city, it is not strange to see the sight of a street that is crowded with vehicles such as bikes, motorbikes and cars. People cannot move, especially in the rush hour and their health is affected by polluted air from exhausted fumes; some get diseases like sore throat, coughing, runny nose,… What are the reasons? The citizens in the city use many personal vehicles to go from one place to another. They aren’t used to travelling by public transport. Maybe because the drivers are careless, or the taxi fare is too high for some people. Besides, the roads are narrow and not in good condition. It makes road users find it difficult to travel from home to work.