gas emission

例句：

1. 1. The factory has been emitting a lot of harmful gases into the air.
   这家工厂一直在向空气中排放很多有害气体。
2. 2. To reduce emissions, we need to switch to electric cars.
   为了减少排放，我们需要换用电动汽车。
3. 3.The government is working on new regulations to control emissions from factories.
   政府正在努力制定新的法规来控制工厂的排放。