There are several solutions that could be applied to tackle the aforementioned problems. The first impossible method is reducing the cost of living by investing money in the building of affordable or social housing and applying policies to stabilize the market. This way could be able to help low-income people and the poors have better living conditions and contribute to preventing the spread of slum areas. Another solution is promoting the use of cleaner public transports by upgrading bus, train, metro systems and introducing lower-ticket prices to encourage people to shift from personal vehicles to public means of transport. Such an action would reduce both air pollution and traffic congestion. In London, for instance, enact congestion charges for drivers could help curb the traffic problem. 
There are several solutions that could  
be applied
 to tackle the aforementioned problems. The  
first
 impossible method is reducing the cost of living by investing money in the building of affordable or social housing and applying policies to stabilize the market. This way could be able to  
help
 low-income  
people
 and the  
poors have
 better living conditions and contribute to preventing the spread of slum areas. Another solution is promoting the  
use
 of cleaner public transports by upgrading bus, train, metro systems and introducing lower-ticket prices to encourage  
people
 to shift from personal vehicles to public means of transport. Such an action would  
reduce
 both air pollution and traffic congestion. In London,  
for instance
, enact congestion charges for drivers could  
help
 curb the traffic problem.