No, sorry if it seems I was changing the question. What I meant is that it crossed my mind try to ask like “Who runs this group?” because I used to think I could ask any question like:
What mean “businessman”? instead of
What does “businessman” mean?
Then, I learn the first sentence wasn’t a question. It is an adjective clause and that’s why I put these examples:
I talked with the one who runs this group
“Who runs this group?” is not a question, is it?
or I just met the girl who lives across the street…
same case…
What means “businessman”? - No good.
What does “businessman” mean?- Good English
I talked with the one who runs this group-- OK
“Who runs this group?” is not a question, is it?- Yes, it is a question; I have already told you that in my earlier post.
I just met the girl who lives across the street.-- OK, too.
“Who + base verb + s” makes questions and also makes relative clauses.