Two factories were closed in an attempt to reduce pollution.

为了减少污染，关闭了两家工厂。

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But Ma doubts the authorities' ad hoc approach -- such as shutting down factories and construction sites to reduce air pollution -- would work in combating desertification.

CNN: Fighting the desert one tree at a time

In Beijing the authorities have shut down some factories and taken cars off the roads to try to reduce the pollution.

BBC: China's coal conundrum as smog worsens