Wire the thermometers up to trigger off an alarm bell if the temperature drops.

把温度计的电线连接上，当温度下降时，就会触发警报。

《柯林斯英汉双解大词典》

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Winter closes in and the temperature drops below freezing.

冬天来临，气温降至冰点以下。

《柯林斯英汉双解大词典》

In that situation, their body temperature drops below thirty-five degrees Celsius.

VOA: special.2009.12.30

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

Statistics show only a 10-33% survival rate for adults whose core body temperature drops below 28degC.

BBC: Skier revived from clinical death

When the body's core temperature drops below 95 degrees Fahrenheit, a mild form of hypothermia takes hold.

FORBES: Magazine Article

Modern mattresses and bedclothes trap the heat that the body gives off as its core temperature drops each night.

NEWYORKER: Up All Night