專(zhuān)業(yè)四級(jí)是針對(duì)英語(yǔ)專(zhuān)業(yè)同學(xué)的重要考試，其真題的參考價(jià)值無(wú)可比擬，希望同學(xué)們能夠吃透真題，通過(guò)專(zhuān)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.