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(chēng)是日歷用來(lái)指代從某個(gè)固定點(diǎn)或事件計算的一段時(shí)間的名稱(chēng)。 - A plane curve formed by the locusof points equidistant from a fixed line and a fixed point not on the line.
拋物線(xiàn)到一固定直線(xiàn)和不在直線(xiàn)上某一固定點(diǎn)等距的點(diǎn)的軌跡所形成的平面曲線(xiàn)。
