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Mismanaged factories caused some of the worst pollution in Beijing, a city choking on toxic smog. But after four years of rigorous action to tackle the problem, Beijing now has its skies back: the city has slashed pollution and is now experiencing its lowest levels of air pollution in years.
Mismanaged factories caused some of the worst pollution in Beijing, a city choking on toxic smog. But after four years of rigorous action to tackle the problem, Beijing now has its skies back: the city has slashed pollution and is now experiencing its lowest levels of air pollution in years. [Last sentence deleted.]