In that experiment, Ledoux conditioned rats to fear a bell by ringing it in time with anelectric shock until the rats froze in fear at the mere sound of thebell.
试验中，勒杜按时闹铃并且电击老鼠直到它们一听到铃声就吓得僵住。
2
The telephone rang in the middle of his important experiment. He ignored the persistent ringing, thinking that any important message would reach him sooner or later.