导火线

例句：

1. 1. The bomb was set to explode at a specific time, like a timer on a clock.
   炸弹被设定在特定时间爆炸，就像时钟上的定时器一样。
2. 2. He was the trigger for the whole incident.
   他是整个事件的触发者。
3. 3. The detective found the clue that led him to the murderer's house.
   侦探找到了线索，引导他找到了凶手的家。