Abstract: 128 five to ten yearold children from Beijing were asked to answer 24 simply questions.Half of the questions were sensible base on general knowledge;the other half were nonsensical for these questions could not be answered based on general knowledge. Accordingly,their correct answers should also be "I don't know" or something like this. The results showed:(1)Chinese children had a tendency to speculate or guess answers when they answered nonsensical questions,and the question format affected children's response tendency,there were more correct answers to open questions then closed questions when answering nonsensical questions. (2) there were differences among ages,older children gave more correct answers then younger on nonsensical questions not included a comparison. (3) children answered rare "No" then "Yes" to closed nonsensical questions not included a comparison,but not to closed nonsensical questions included a comparison.

Key words: tendency to speculate, negative response bias, nonsensical questions, question format