The last question of the homework refers to a table concerning child utterances containing not, and gives the table in the same form as the others, crossing inflection in the stimulus with inflection in the child’s utterance.

“But wait,” you might say, “you don’t get inflected verbs with not in English. What’s going on?”

Indeed, a verb negated with not in English is not inflected, the inflection is carried on do: He does not go. The trick here is revealed by looking at (8b), which is the stimulus sentence for the inflected-not condition. What the researchers did is put the not in a higher clause: Do you think that he goes, or don’t you think that he goes? So, goes is inflected in the stimulus sentence, as advertised, and children (like adults) interpret this as meaning the same thing as Do you think that he goes, or do you think that he doesn’t go?—and, it seems, answer accordingly.