学进去

   New York, Paris and other big cities are ______ places to live in. There are many interesting things to see and to do. You can go to ______ kinds of museums, plays and films. You can also buy things ______ all over the world.

______ there are serious (严重的) problems (问题) in big cities too. It is expensive (昂贵的) to live there, and there are ______ people in some places of big cities. Every year many people move to the cities to find jobs, to ______ at good schools and receive (受到) good medical care (医疗服务). But sometimes these people cannot find work or a good place to ______ in. Also it is ______ to keep the cities safe and clean. Some people enjoy living in big cities, others ______. Before moving to a big city, you should ______ the problems of living there.