permanent bipolar magnet的用法和樣例：
例句
- A permanent magnet assists closing and latches the breaker in the closed position.
一個(gè)永久磁鐵幫助跳開(kāi)關(guān)閉合并鎖定在閉合位。 - Other objects become magnetic only when in a magnetic field caused by a permanent magnet or an electromagnet.
其它物體只有在處于永久磁鐵或電磁鐵形成的磁場(chǎng)中時(shí)才具有磁性。
