to talk; to speak; to converse
To converse fluently in English
They were talking in Chinese
I don't want to speak to you !
I'd like to talk to you in private; I'd like to speak to you alone
May I speak to X?; Please put me through to Mr X
Professor X will speak/talk about diabetes; Professor X will give a talk on diabetes
to speak; to address
Speaking at the ceremony/Addressing the ceremony, the director highlighted the importance of the ISO 9001-based quality management