"We have teams of people just going door-to-door ensuring that every child under five is vaccinated with drops."

VOA: standard.2010.08.02

It could be that what you want just drops into your lap without you knowing about it.

很有可能你想要的东西,在你不经意间就到来了

耶鲁公开课 - 博弈论课程节选

If the temperature drops below a certain level it sends a signal, 'turn on the heat', and that signal stays on until it gets a negative signal to turn off.

如果温度降到一定程度以下时,探测器会发送一个信号,打开加热器,直到加热器再收到关闭的信号,它就会一直开着

耶鲁公开课 - 生物医学工程探索课程节选

The World Health Organization currently recommends that patients begin taking AIDS medicines, called antiretroviral drugs, when symptoms appear or when their CD4 count drops below 200.

VOA: standard.2010.07.21

It's really,really important that every time we reach every child with polio drops."

VOA: standard.2010.08.02

It was one man's vision that if just two drops, from a bottle like this one, could prevent children from getting the disease, that global eradication could be within reach.

VOA: standard.2010.08.02