•Some sounds cannot be detected by the human ear.有些声音是人的耳朵无法察觉到的。

•Financial experts have detected signs that the economy is beginning to improve.金融专家已经注意到经济开始有好转的迹象。

•High levels of lead were detected in the atmosphere.经检测发现大气中铅的含量很高。

•Radar equipment is used to detect (= find the position of) enemy aircraft.雷达装置用于探测敌机的位置。