We attended this year's United States Air Guitar Championships in Washington,D.C.to learn more about this unusual activity.

VOA: special.2009.08.14

I can't think of any activity I'd want to do forever.

我想不出一样希望永远从事的活动。

耶鲁公开课 - 死亡课程节选

The C.D.C.defines physical activity as anything that gets your body moving.

VOA: special.2010.06.08

G.D.P.is the widest measure of economic activity.

VOA: special.2010.02.12

Users visiting the website created for this study were asked to enter their weight, the food they'd eaten, and their physical activity.

VOA: standard.2010.07.30