A thought like that one about the air could be put away.

There was a certain something about the air in the city.

They did not need to worry about food or air.

"You must be right about the air," she said, then looked around.

"I know about the air," she says to his back as he walks away from her.

"There is something wrong about the very air we breathe!"

But what about the air coming in through the vents?

"There's a reason artists come to the Island to work, something about the air, the space and the light," she added.

These days in Beijing, everyone is complaining about the air.

Now there is increased concern about recycling and clean air.