Meteorologists and aviation authorities are monitoring wind direction and the ash cloud's movement from Iceland to determine where and when to shut down airspace in Europe.

VOA: standard.2010.04.15

Movement down a concentration gradient occurs fairly rapidly over short distances like a micron or so, like the size of a bacterium.

顺浓度梯度扩散在一微米左右的短距离内,相当迅速,一微米相当于一个细菌的大小

耶鲁公开课 - 生物医学工程探索课程节选

We were going down in the first movement. Now we're going-- It's going up and instead of having just the violins playing we have the trumpets, the heroic trumpets, so it sounds very triumphant.

第一乐章中,我们曾情绪低落,但现在,情绪正高涨,刚才小提琴演奏的部分,换成了小号,豪情万丈的小号,听上去有种胜利的喜悦

耶鲁公开课 - 聆听音乐课程节选

The counterterrorism operation in Chechnya was instituted in 1999, when Russia sent troops for the second time since the collapse of the Soviet Union to put down a local separatist movement.

VOA: standard.2009.04.16

It might bend and bow, that is it's not the forces of nature like the movement of the river that's knocking the bridge down, but it's just the failure of these materials over time, that they don't last as long as they might.

这桥可能会折断,不一定是洪水这样的自然灾害,导致了桥梁的坍塌,可能只是因为建桥的材料老化,这种材料没有那么持久耐用

耶鲁公开课 - 生物医学工程探索课程节选

The results are mixed. For example, the report says progress is being made in bringing down child deaths, but there has been little or no movement in maternal and newborn health.

VOA: standard.2009.05.21