Don't be distressed if you're unfamiliar with it.

如果你们不熟悉这个，没关系的。

耶鲁公开课 - 现代诗歌课程节选

The other day, I was looking for my bank in an unfamiliar neighborhood.

前几天，我在一个不熟悉的社区寻找银行。

Is there 课堂 - SpeakingMax英语口语达人

If unfamiliar, these are the mechanical computer devices that you have to use to buy a ticket on the T these days and there was one of these really awkward but touching situations where it was clear that this woman had no idea, you know, what to do, how to get from here to here, and I could see her just staring at the turnstiles that you're supposed to go through to get into the subway.

如果不熟悉，这是机械计算机设备,当今你必须使用它们来买地铁票,它们实在是难操作的,这个令人同情的情况是,明显这位老太太不知道怎样操作，怎样从这一步到那一步,我看见她只是凝视着,地铁的栅门口。

哈佛公开课 - 计算机科学课程节选

Because we obviously can't, in any course, or even any set of courses, tell you everything you'll ever want to know in life we've seeded some things in this program that will be unfamiliar, so during the time you're studying the program, get online, look it up, figure out what they do.

因为在任何一门课上或者几门课上，我们都不可能告诉你，所有你想知道的事情,我们在这个程序中,加上了一些你们不熟悉的东西，所以在你们研究这个程序的时候，你们可以上网找资料，弄懂它是干什么的。

麻省理工公开课 - 计算机科学及编程导论课程节选