Fill in the blank to complete the passage.

Modern cities (1) ______over the world face the same problems. One of them is poor housing. People often live in old houses or huts that don’t have electricity or sanitation. As city population (2)__________ , governments don’t have the money to (3) ____________modern apartment buildings. Cars and industries are (4) ____________city air and rivers more and more now. Waste that people throw away is burned or ends up in landfills. All of this makes modern cities an (5)____________ place to live in. Especially during morning and evening rush hours cities become packed (6 )____________ vehicles. Daily traffic jams make it impossible for people to get to work in time. City authorities are (7)____________ more and more money on public transportation and are taking other steps to (8)____________ traffic in cities.

Cities of today face many social (9)___________ . Crime, alcoholism and drug addiction is especially high in cities. Many young people are unemployed. Government organizations work hard to get rid of poverty. They try to give such people (10) better___________ and jobs.

Cars and industries are (4) ____________city air and rivers more and more now.