magnet keeper

例句：

1. 1. The magnet keeper is used to keep the magnets in place.
   磁体保持器用于将磁铁固定在适当位置。
2. 2. The magnet keeper was designed to prevent the magnets from moving around.
   磁体保持器被设计来防止磁铁移动。
3. 3. The magnet keeper was removed from the machine before it was turned on.
   在机器启动前，从机器中取出了磁体保持器。