Read the passage and fill in the blanks with proper words.(在短文空格内填入恰当的词，使短文通顺，首字母已给）

New York, London, Paris and other big c【小题1】 are interesting places to live in. There are many good things to see and to do. You can go to d【小题2】 kinds of museums. You can also go to shopping centers to buy things from all over the world.

But there are serious problems in big cities, too. The cost of l【小题3】 is high and there are too many people. Every year, many people move to big cities to find jobs, to study at good schools, and to get good medical care. But sometimes it is difficult to live in big cities. Too many people in a city make it hard to keep it safe and c【小题4】.

Some people e【小题5】 living in big cities, while others do not. Before people move to a big city, they should think about the problems of living there.