Muller remembers hearing violent knocks at the door of her Paris apartment late one night.

VOA: standard.2010.04.10

So, what you do is you set up a couple of displays, one where the block is stopped, the other one where you take this away with a trap door and it keeps going.

所以,你可以设计几个演示,一个是木块被挡住了,另一个是用活门把木块挪开,使得屏板继续上升

耶鲁公开课 - 心理学导论课程节选

The crowd outside the courthouse watched anxiously as one by one, each with a canvas-covered bed, backed up to a courtroom door and, out of the view of onlookers, deposited handcuffed defendants for a brief appearance before a judge.

VOA: standard.2009.05.25