clean air

• 新鲜空气,纯洁空气

clean air的用法和样例：

例句

1. He sniffed the fresh morning air.
   他吸进早晨的新鲜空气。
2. "A sweet temper" is a figurative expression, but "sweet coffee" is not.
   "甜蜜的性情"是个比喻的说法，而"甜咖啡"则不是。