扣环

例句：

1. 1. The lock on the door was broken, so we had to use a key to open it.
   门的锁坏了，所以我们不得不用钥匙打开它。
2. 2. The car's engine is not working properly, and I need to replace the fuel cap to fix it.
   车的引擎工作不正常，我需要更换燃油盖来修理它。
3. 3. The child was wearing a safety belt, which helped prevent him from being thrown from the car during the accident.
   这个小孩系着安全带，这在事故中帮助他避免了从车里被抛出来。