A set of questions which are asked more than once where some aspect of each question is varied. For example:
Q10. Which of these brands have you purchased in the last week? Tick all that apply.  Coke  Pepsi  Fanta  None of these LOOP OVER Q11 AND Q12 FOR ALL BRANDS SELECTED IN Q10 Q11. Where were you when you last purchased INSERT BRAND FROM Q10? Q12. Who were you with when you last purchased INSERT BRAND FROM Q11?