他在伦敦没有认识的人。

He doesn't know anybody in London.

youdao

不幸地，到了一个新城市，没有认识的人，一开始会很孤独。

Unfortunately, moving to a new city without any of the people you know can be lonely at first.

youdao

我所认识的人当中，没有一个人如此富有或者成功。

No one else of my acquaintance was as rich or successful.

《牛津词典》

So if you haven't already, just glance at the person next to you, or say hello if you don't know them.

如果你还没有做好，那就看看你旁边的人,如果你不认识他们就跟他们打个招呼。

哈佛公开课 - 计算机科学课程节选

but for other people I know that didn't get into a place like this, you know, they...

但是别的我认识的人没有来到这儿，你知道，他们……

不平等的入学基准 - SpeakingMax英语口语达人

I don't think I know anyone who had an extensive experience in the war.

我觉得我认识的人当中,没有人在战争中有很多的经历。

普林斯顿公开课 - 人性课程节选