Suddenly,without warning, a heavy mass of snow dropped down.

VOA: special.2010.05.01

It dropped dramatically in the period from 1954-- this is these filled black bars refer to this axis, polio cases per 100,000 population dropped down to only three or four cases by 1956.

患病率在一九五四年后的,一段时间里急剧下降,该坐标轴上的这些黑色柱形图表明,到一九五六年,小儿麻痹症的发病率,已经降低至每十万人中仅三到四人发病

耶鲁公开课 - 生物医学工程探索课程节选

"Just kind of uh, just stepped off the cliff and said 'okay where's that microphone.' Made a short couple of comments and then put the mic down and dropped down on one knee and.

VOA: standard.2010.02.27

the rate has dropped to 83 per 1,000,down sharply from 124 a decade ago.

VOA: standard.2009.11.10

The rocks were tumbling down around us. We dropped our tools and ran."

VOA: standard.2010.04.02