填空题

Urban life has always involved a balancing of opportunities and (11) against dangers and stress; its (12) force is, in the broadest sense, money. Opportunities to make money mean competition and competition is stressful; it is often at its most intense in the largest cities, where opportunities are greatest. The presence of huge numbers of people inevitably involves more conflict, more traveling, the (13) of public services and (14) to those (15) and criminals who are drawn to the rich pickings of great cities. Crime has always (16) in the relative anonymity of urban life, but today’s ease of movement makes its control more difficult than ever; there is much evidence that its extent has a direct relationship to the size of the communities. City (17) may become trapped in their homes by the fear of crime around them. As a defense against these developments, (18) :contacts with other people are generally made brief and impersonal; doors are kept locked; telephone numbers may be ex-directory ;Journeys outside the home are usually hurried, rather than a source of pleasure. (19) .Furthermore, all these defensive forms of behavior are harmful to society in general; they cause wide spread loneliness and destroy the community’ s concern for its members. (20) .