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BEIJING—The sky is gray and air smells strange．It's another day of smog．On Saturday，heavy haze (霾) still covered north and east China．Highways were closed and1 couldn't take off on time．
The smoggy weather 2 the country's land from north to south，including Beijing, Hebei， Shandong，and 60ther provinces．People could only see clearly 3 than 50 meters in some areas．
Cities 4 Shanghai and Nanjing have been covered by the gray sky for the past several days．Many walkers in the street had to wear 5．In the Lukou airport in Nanjing more than 60 flights were canceled on Saturday 6 the haze，which also made primary and middle schools and kindergartens stop 7on Thursday and Friday in Nanjing．
The office worker of Environmental Protection said earlier this week that there were several 8 reasons behind the widespread haze：unpleasant weather conditions making9 difficult for smog to disappear，automobile exhaust(尾气)，and coal use for winter heating．
To fight pollution，the Chinese government now plans to clean up the air by cutting coal use，10 some factories，and removing 6 million old cars from the roads．
“We must face up to the facts，”said Yan Naiqiang，a professor of environmental science at Shanghai Jiao Tong University．“The treatment of smog will be a long fight． From now on，if we use buses or cars less and do more tidin9，we believe a clear sky is not a faraway dream．”
