fail

Compared meaning: stop working, especially for machines or devices (verb).

比较义项：（机器、装置等）停止运转、失灵（动词）。

• die

  Informal, common for engines, batteries, or electronics that suddenly stop working or run out of power; evokes a sudden, often unexpected stop.

  口语化，常用于引擎、电池等设备突然停止运转或电力耗尽，带有“突然、意外停止”的意味。

  The old truck's engine died on the highway, and we had to call a tow truck.

  那辆旧卡车的引擎在高速公路上熄火了，我们只好叫拖车。

• break

  Suggests something stops working because a part is damaged or broken, so it needs repair; neutral in tone and common in everyday speech.

  强调因某个零件损坏而无法使用，需要维修，语气中性，日常口语中很常见。

  The zipper broke, so my backpack won't close properly anymore.

  拉链坏了，所以我的背包现在没法好好合上了。

• fail 本词

  More formal and serious, typically used for critical systems, mechanisms, or safety equipment that stop working correctly; suggests higher stakes than die or break.

  语气更正式、更严重，常用于关键系统、机械装置或安全设备的失灵，比 die 或 break 涉及的后果更重大。

  The brakes failed going downhill, which almost caused a serious accident.

  下坡时刹车失灵了，差点酿成严重事故。

Die, break, and fail can all mean a machine stops working. Die is informal, used for engines or batteries. Break means a part is damaged; neutral in tone. Fail is more formal, for serious systems. Not compared: die (death), break (break apart), fail (not succeed).

这三个词在“停止运转、失灵”这一意义上相近，但语域和严重程度不同：die 多用于口语，指引擎、电池等突然“熄火”或耗尽；break 强调因零件损坏而不能用，语气中性偏口语；fail 更正式、多用于关键系统或机制的失灵，后果通常更严重。这里不比较 die 的“死亡”义、break 的“打破、休息”义，也不比较 fail 的“失败，不及格”义。