前一的用法和樣例：
例句
-
乘客至遲應在班機起飛前一小時辦理登機手續。
Passengers should check in one hour before their flight time at the latest. -
你以前一定見過他。
You must have seen him before. -
雖然我非常希望增加體重，但我仍然像以前一樣的瘦。
Much as I hope I may gain weight, (yet) I am still as thin as before. -
聖誕節前一周，孩子們到各家各戶去唱聖誕頌歌。
The children went carolling during the week before Christmas. -
來訪者在中午前一會兒離開了。
The visitor left a little before noon. -
老人前一天晚上停止了呼吸。
The old man ceased breathing the night before.
