Over half the world’s people now live in cities. The latest “Global Report on Human Settlements” says a significant change took place last year. The report【C1】______this week from U. N. Habitat, a United Nations agency.

A century ago,【C2】___than five percent of all people lived in cities.【C3】the middle of this century it could be seventy percent, or【C4】six and a half billion people. Already three-fourths of people in【C5】countries live in cities. Now most urban population【C6】___is in the developing world.

Urbanization can【C7】___to social and economic progress, but also put【C8】on cities to provide housing and【C9】. The new report says almost two hundred thousand people move【C10】cities and towns each day. It says worsening inequalities,【C11】by social divisions and differences in【C12】, could result in violence and crime【C13】___cities

plan better.

Another issue is urban sprawl(无序扩展的城区). This is where cities【C14】___quickly into rural areas, sometimes【C15】___a much faster rate than urban population growth.

Sprawl is【C16】___in the United States. Americans move a lot. In a recent study, Art Hall at the University of Kansas found that people are moving away from the【C17】cities to smaller ones. He sees a【C18】___toward “de-urbanization” across the nation.

【C19】___urban economies still provide many【C20】___that rural areas do not.

【C4】