I have no idea why I remember some stuff forever and forget some stuff right away, although I think the more important a piece of information is the more likely I will be unable to hang onto it. And music might help. When I was in the fourth or fifth grade we had to learn all the helping verbs by singing the aptly-named "Helping Verbs Song." It goes something like this:
"Am, is, are, was, were, has, have, had
Do, does, did, can, may, might, must
Shall, will, should, would, could."
The helping verbs, ladies and gentlemen! Thank you very much.