Let's consider this situation. A mother asks her child, "Who ate this apple?" Then her son replies, "I didn't eat." In this situation, is "eat" an intransitive verb when "the apple" is omitted? I think "eat" is transitive verb originally. What do you think?
I will try to avoid begging the transitive question.
When eat is used without a direct object it usually has a somewhat different meaning than it does when used with a direct object: something closer to ‘take a meal’. For instance:
- You're in plenty of time, we haven't eaten yet = Dinner has not yet been served.
- No, thanks, I ate already = I already had lunch.
In some circumstances, to be sure, it does imply eat something:
I'm famished, I haven't eaten at all today = I haven't eaten anything today.
But U.S. children would not answer the question Who ate this apple?† with I didn't eat—that would be non-responsive, because it answers a different question. They would be more likely to say something like I didn’t eat it!‡
†Actually, this question would probably not be asked, since the apple is no longer present. The question would probably be Who ate that apple?
‡Actually, they would probably answer Not me!—which would come out Dobbe!, because their mouth would be full.