Reuters: China pledged on Sunday that it will make sure that 60 percent of its cities meet national pollution standards by 2020, with pressure growing to make cities liveable as hundreds of millions of migrants are expected to relocate from the countryside. China's environmental problems such as pollution and water scarcity are expected to intensify as rapid migration pushes urban infrastructures to the limit. Almost all Chinese cities monitored for pollution last year failed to meet the standards. The...