專業(yè)四級是針對英語專業(yè)同學的重要考試，其真題的參考價值無可比擬，希望同學們能夠吃透真題，通過專四。
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medium-sized
"All large and medium-sized Chinese cities will have greater air quality monitoring by 2010." says a government official. The government has spent 150 million yuan on air quality monitoring systems across China since 2000 when officials began paying greater attention to air quality monitoring. More than 220 cities now have air quality monitoring systems and 42 others will have systems in place by the end of this year.