After I leave the box and step back into my cage, I get an idea, a good one.
I tell Bob he can sneak into my box with me and live at the zoo.
“Have you forgotten? I’m a wild beast, Ivan,” he says, sniffing the floor for crumbs. “I am untamed, undaunted.”
Bob samples a piece of celery and spits it out. “Besides, they’d notice. Humans are dumb, but they’re not that dumb.”
The above paragraph comes from the book The One and Only Ivan page 251. After reading this, I have a question: Can I change "Have you forgotten?" to "Did you forget?" or not?
I know both of them are grammatically correct. But are there any differences between them? When should I use simple past tense and when should I use present perfect tense?