But no evidence demonstrates that the duration of outdoor exposure - in places where people can move freely about - is long enough to cause substantial health damage.

但还没有证据表明，当人在户外自由移动时，身体接触到的烟气的残余，确实多得能够伤害健康。

youdao

But after a few days they arrive at an altitude, about 125km up, which is so rarefied that an ion can move freely about.

但几天之后，它们会达到大约125km的高度，在这里空气稀薄到使离子可以自由的运动。

youdao

To move about or flow freely, as air.

像空气或液体一样自由流动。

youdao

It is our home market in which goods, services, capital and people can move about freely.

BBC: Get off the fence, prime minister!

In the mid-1990s, that would change, as browsers, such as Netscape (which AOL ultimately bought, then essentially killed) and Internet Explorer, let us move freely about the Web.

MSN: AOL: You've got irrelevancy?

On the trade front, after the Asian crisis ASEAN redoubled efforts not just to create free trade in merchandise goods but, by 2015, an ASEAN Economic Community in which goods, skilled workers and capital are supposed to move freely about.

ECONOMIST: Regional economic integration has a long, long way to go