You can accept someone's apology by saying:

That's all right!
It's perfectly¹ all right.
It really doesn't matter.

Here are some expressions that are often used in meetings.

If you're in a meeting, you can find out what the other people in the group think by saying:

What are your views on this, John?
Mr Brown, what do you think about this?
Do you agree, Mary?
Ms Smith, what's your opinion?

If you want to interrupt² someone and put forward your own opinion you can say:

If I could just make a point here…
Sorry to interrupt, but I’d just like to say that…
Could I make a suggestion?
It seems to me that…#p#

If you want to find out if the others in the group have understood or if they agree with you, you can say:

Do you see what I mean

 Don't you agree, Simon?
Don't you think so, Mrs Robinson?
Are you with me?
Are we unanimous³?
Does anyone object?

If you don’t understand what someone has said, you can say:

Sorry, could you say that again, please?
Sorry, I didn't quite understand.
I'm sorry, I didn't catch what you said.
Sorry, I'm not quite with you.