This is coming a bit late, but in case you had been puzzling over this on homework #3, the third question refers to how people did with respect to sentence 5. Unfortunately, the autonumbering I used to set up the questions to be answered continued with the example French sentence (giving the glosses) at the very end of the homework, and so that was labeled “(5)”. Question (3), however, is intended to refer to the fifth sentence of the test.

The fifth sentence of the test is in an order that is ungrammatical in both Dutch and French, and the 1st graders mostly rejected it (correctly). The 3rd graders and adults also rejected it (correctly). But the 2nd graders mostly accepted it (incorrectly). So the question was to think about why the 2nd graders might have erroneously been accepting it, even though they used to reject it and would come to reject it again later.