I forget" vs "I forgot" vs "I have forgotten"

English as a Second Language English Vocabulary, Grammar and Idioms
1

A: “What’s the title of the movie you saw yesterday?”
B: “I forget.”/“I forgot.”/“I have forgotten.”

Is there any difference among “forget” and “forgot” and “have forgotten” in this case? I

I’m especially curious about “I forgot,” because English grammar tells you it means, at least literally, that the speaker forgot the title at some point in the past and may or may not remember it now. So the logical conclusion would be that this form is not correct, at least to the ears of grammatical sticklers, because it doesn’t address to the question of whether or not the speaker remembers it now. But I hear people say “I forgot” all the time. Maybe it’s another example of the past tense being used in place of the present perfect (eg. “Did you eat yet?”/“Have you eaten yet”) and they actually mean “I have forgotten” when they say “I forgot”?

Can anyone clear up my muddled mind?

Carrie

2

There is no difference in intent in B’s responses. All are common, and choice remains with the speaker and his/her habit of use. A native speaker does not ‘mean’ one verb form and use another. Grammar follows speaker use, not vice versa. Here, all 3 verb forms are used to mean that the speaker cannot supply the movie title at the moment.