Say and switch is a cooperative structure in which partners sequentially take turns responding to a question or discussion topic at signaled (and sometime unpredictable) intervals.
Once the topic has been given, one partner speaks and the other listens, when the switch occurs, the challenge for the second partner is to continue (or complete) the first partner's line of thought before introducing new ideas.
As an alternate, before the second members speaks, she can formulate what the person has said by finishing the following sentence: 'What I have heard you say is that...'
Say and Switch as a cooperative structure is particularly useful for reviewing a material, rehearsing or checking for understanding.
In such cooperative structure both members of the group are accountable to participate.
It one is looking to extend such activity, it is possible to say that 'Now that I have heard you say.... I wonder ...' in order to get the conversation going and provide feedback to one another.