FAQs About the word once in a blue moon

極罕見

very rarely

不經常,少,偶爾,很少,有時,絕不,永不,時不時地,很少,零星地

總是,永遠,頻繁地,一般,經常,通常,例行地,通常,始終,不斷地

on-and-off => 時有時無, on top of => 在…之上, on tiptoe => on tiptoe, on the warpath => 處於戰備狀態, on the surface => 表面上,