While students in Hainan are quite used to clear skies, Beijing teenagers are not so 
lucky. As another warm winter approaches, the city can expect the normal clouds of smoke 
caused by air pollution. 
    But things could start to get better soon. The government is co-operating with a US-
based environmental protection agency to update existing buses and trucks with clean fuel 
technology. The new technology could reduce air pollutants in existing diesel vehicles (
) by 40 per cent. The programme will begin by testing buses in Beijing to see if the 
technology can be applied to them. 
    "We encourage the development of public transportation. But at the same time we need 
to reduce pollution from them," said an official. 
    Efforts are being made to improve the capital's environment with tighter controls on 
emissions  . Some heavily polluting factories and construction sites, such as those 
owned by the steel giant Shougang Group, have been asked to cut production in November 
and December or be closed. Beijing was the third polluted city in the world at the end of 
last century, according to the UN. But thanks to recent measures, the capital has made 
some progress. Last year 224 clear days were rated as having good air quality. In 1998 
the air quality index   gave just 100 days as good. 
    "I am glad to see an improvement," said a Senior 1 boy living in the northwest of 
Beijing. "Compared to other places, the air quality of Beijing is still worrying though.
I hate the pollution. Once I was riding my bike in the morning when I almost had a traffic
accident because I couldn't see a car only metres away from me in frog." 
    In early October, the skies were covered by such a thick fog that a display show by 
the visiting French air force was called off. 
    Rapid development, industry, traffic fumes   and sandstorms from the desert all 
contribute to the city's bad air.
Which is not correct according to the passage?
Beijing's air quality is getting worse and worse. Development, industry, traffic fumes and sandstorms are all the causes of bad air 
   quality. Clouds of smoke in the sky is the common feature in the winter of Beijing. The government is making every effort to stop air pollution.