1. Expression：Dear John letter

Explanation：A letter sent, typically from a woman to a man, to end a romantic relationship.（绝交信）

Example：Mike was clearly upset when he received a Dear John letter from his girlfriend, Caroline. He thought their relationship was going well and didn't expect it to end so suddenly.

当迈克收到他女朋友卡洛琳的绝交信时，他显然很心烦意乱。他认为他们的关系发展很好，没想到会这么突然就结束了。

Mail call was usually a happy time in the military barracks, except for the unlucky soldiers who got Dear John letters from their sweethearts back home.

在军营里，邮电通话是一段快乐的时光，除了那些倒霉的士兵接到他们家乡恋人的分手信。

Her Dear John letter finally caught up with me while I was awaiting discharge.

她的绝情书终于在我等候复员时送到我手中。

By the time he got the Dear John letter from his girl friend, he was climbing the walls.

他接到了女友的绝交信，心中极度烦恼。

2. Expression：hit the John

Explanation：To go to a toilet to urinate or defecate. （上厕所）

Example：Be right back, I've gotta hit the John.

马上回来，我要去上厕所。

Excuse me for a minute——I must hit the John before we go out.

请稍等—出去前我得先上厕所。

3. Expression： stage-door Johnny

Explanation：A man who spends a lot of time at a theater so as to seek the romantic attention, favor, or company of an actress.（经常去剧院捧女演员的男子）

Example：Ms. Gabler is such a stunning beauty that she always has some stage-door Johnny or another waiting for her after the curtain falls each night.

Gabler小姐是如此惊艳的女子，所以她拥有去剧院捧她的男子，或者是每晚落幕后有人在等她。