 When you want people to speak more or share examples or share their thoughts, you can start off explaining the activity, sharing an example of your own and then say the words, what else? Who else has something? Who's got something else to add? On the other side of this, when people have engaged enough and maybe are now speaking too much and discussion is breaking out, you can close this off by using the flip side of this sentence. Is there anything else? I don't think there needs to be anything else is closing down the conversation.