Recent research emphasises the importance of how child witnesses are interviewed. Studies have shown that children can give reliable testimony if interviewers comply with instructions such as avoiding suggestive questioning and not giving feedback on the child's answers. Positive feedback suggests that there are right (and wrong) answers whereas negative feedback could urge children to change their answer. In this article we analyse questions that are prefaced by 'maar' (= Dutch 'but'), questions that are often associated with disagreement and objection and might give negative feedback. Based on the analysis of seven police interviews with child witnesses, we show 1) how these questions can treat a preceding answer as insufficient and how they project the need for another answer, and, 2) how these questions can differ a) to what extent they guide children to change their answer, b) in how they attribute responsibility for the insufficient answer to an inadequate question or to something else (e.g. the child's attention) and c) in how much pressure they exercise. © 2014, EQUINOX PUBLISHING.