They store the energy mechanically by rotating mass around an axis.

它们通过质量绕轴旋转机械存储能量。

youdao

These changes are caused by anything that moves mass around on the Earth.

地球上物质体的任何移动都会引起这些变化。

youdao

The amount of angular momentum, say, a spinning skater has depends on both the speed of rotation, and the weight and distribution of mass around the center.

角动量的大小，取决于旋转中的滑冰选手的旋转速度、体重和绕旋转中心的质量分布。

youdao

Cities in the United States and Europe have increased security in and around their mass transportation systems.

VOA: special.2010.04.03

In the wake of the bombings, cities in the United States and Europe boosted security in and around their mass transit systems.

VOA: standard.2010.03.30

It also runs Disaster Victim Identification training for police offers to help them deal with mass fatalities around the world.

BBC: Crime writers back Dundee University ?1m morgue fund

He envisions a slimmed-down Ford Motor that pitches one mass market brand around the world: Ford.

FORBES: Back To The Future

These winds are generated in a swirling mass of matter around the equatorial region of a black hole, the accretion disk.

CNN: Black holes in a new light