我咳嗽不止。

I can't stop coughing.

2010年8月的第一周，当莫斯科市民在一片厚厚的烟尘之下咳嗽不止时，一种无色无味的气体的大气浓度已经到达了危险的水平。

Even as Muscovites choked under a blanket of thick smoke in the first week of August 2010, concentrations of a colorless, odorless gas spiked to dangerous levels.