Common Sense Teaching ESL is the website of ESOL book author David Kehe, who has written excellent books on conversation strategies. On his site there are articles about such strategies as clarification, rejoinders, follow-up questions, and other moves that we make in conversation. These can be difficult to teach because those of us who have grown up speaking the language do these things unconsciously, and but they’re important because they’re part of the social aspect of language. David recently led a discussion of teaching student-centered conversation on the LINCS discussion board, and you can read it here: https://community.lincs.ed.gov/group/20/discussion/discussion-david-kehe-teaching-learner-centered-conversation.