Downward compression, upward compression, expansion. and it’s to get these mixed up. But I hope you’ll forgive me if I try to simplify...

A hook is an element in your arrangement. That’s not to say it can’t also be a chorus, but if we choose to make a hook mean the same...

There is a reasonable chance that the first minor chord you learned to play was an a minor. That means an E seven was probably not far...