Advanced grammar book by Martin tells me that I can use the simple present to highlight an event which is often used after past tenses and with a phrase such as all of sudden and suddenly. It says there it's commonly used in narratives and anecdotes.
I was sitting in the park, reading a newspaper when all of a sudden this dog jumps at me.
Why is it not jumped instead? Can I still use jumped? Since the book mentioned, "after past tenses" does it mean it applies to past perfect, past future, and other tenses involving the past?