越来越多的专家相信移民对城市的建设起到积极作用。然而，越来越多的城市居民却怀疑这种说法，他们抱怨民工给城市带来了许多严重的问题，像犯罪和卖淫。

10. Many city residents complain that it is so few buses in their city that they have to spend much more time waiting for a bus, which is usually crowded with a large number of passengers.

许多市民抱怨城市的公交车太少，以至于他们要花很长时间等一辆公交车，而车上可能已满载乘客。

11. There is no denying the fact that air pollution is an extremely serious problem: the city authorities should take strong measures to deal with it.

无可否认，空气污染是一个极其严重的问题：城市当局应该采取有力措施来解决它。

12. An investigation shows that female workers tend to have a favorable attitude toward retirement.

一项调查显示妇女欢迎退休。