9S

people’s desire to look for better education or well-paid jobs in cities, so _______ happens

too many vehicles on the roads at the same time

too many people living in one place

the air released from our cars

the result of the deprivation (sự thiếu thốn) and unstable conditions

the increasing expenses when living in big cities

the consequence of burning fossil fuels, cutting down rainforests and farming livestock

the times during which the majority of people commute

the lack of houses or shelters

the lack of necessary skills to do the jobs leads to _______