It is untrue to say that something like this could never happen again.

说这类事情再也不会发生是毫无事实根据的。

《牛津词典》

You can say something like, "I remember you said something very interesting yesterday and wanted to talk about it some more, but I'm new here and don't remember your name yet. Would you mind telling me again?"

你可以这样说：“我记得你昨天说了一些有趣的事情，还想多谈谈，但我是新来的，还不记得你的名字。你介意再告诉我一遍吗？”

youdao

Jane had already written a few lines to her sister to announce their safe arrival in London; and when she wrote again, Elizabeth hoped it would be in her power to say something of the Bingleys.

吉英早已来了一封短简给伊丽莎白，信上说，她已经平安抵达伦敦；伊丽莎白希望她下次来信能够讲一些有关彬格莱家的事。

youdao

They say Charlie Brown has failed again to do something right.

VOA: special.2009.10.25

For any one of those, we could again run an argument where we say, "Look, here is something that needs explaining.

对于以上任意一个,我们都能再次提出一个论证,看啊,这里有某个东西需要解释

耶鲁公开课 - 死亡课程节选

Then again, if you are not certain of something you can say "I'm not sure."

同样的，如果你对于一件事没有把握，你可以说“I'm not sure.”

I'm sure 课堂 - SpeakingMax英语口语达人

" Again, you should say something like "My total compensation is in the high five figures, but every company has a different mix, so tell me how you see the compensation for this position being structured.

CNN: Life skills your mother never taught you

Morrie has something to say about those who want to be young again.

CNN: Tuesdays with Morrie

And tax reform, again, as I said, is something that Republicans say they're for.

WHITEHOUSE: Press Briefing by Press Secretary Jay Carney,