包裝上的那個日期
這一組就是核心畫面本身：真的印在食品上的那一行字。
noun · B1
The date printed on a food package saying the last day the shop should sell that item.
有效販售期限
核心畫面
One way to hold this phrase: a small date stamped on a packet, saying sell me before this day. It is a line drawn in time — on one side the thing is fresh and wanted on the shelf, on the other side it is taken off. Once that picture is in your head, English can stamp the same invisible date on anything at all: a phone, a joke, a set of rules, a person.
可以想成：包裝上印的一個小日期，上面寫著「請在這天以前把我賣掉」。它像在時間上畫了一條線。線的這一邊，東西還新鮮、還…更多收起
可以想成：包裝上印的一個小日期，上面寫著「請在這天以前把我賣掉」。它像在時間上畫了一條線。線的這一邊，東西還新鮮、還擺在架上；線的那一邊，就被收走了。這個畫面一旦記住，英文就能把這個看不見的日期蓋到任何東西上——一支手機、一個笑話、一套規定，甚至一個人。Two branches
把這個日期蓋到別的東西上
同一條時間線，只是換了對象：東西還能用，但已經被時間推到線的另一邊了。
noun · B2
The point after which someone or something is no longer new, useful or interesting. It is nearly always used in the phrase past its sell-by date, and it can be said about people as well as about things and ideas.
該退場的時候（比喻）