immovable point的用法和樣例：
例句
- The era name is the name a calendar uses to refer to a period of time reckoned from a fixed point or event.
紀元名稱是日曆用來指代從某個固定點或事件計算的一段時間的名稱。 - A plane curve formed by the locusof points equidistant from a fixed line and a fixed point not on the line.
拋物線到一固定直線和不在直線上某一固定點等距的點的軌跡所形成的平面曲線。
