How have cadences been used in the last 100 years?

Listening to All the Things You Are Hammerstein/Kern

Lead sheet contain chords and melody

Jazz uses the "real book" which is a collection of jazz standards, and it's a collection of lead sheets

251 refers to the chord progression ii -> V7 -> I

They are often chained together, the I is changed to minor and treated as the ii chord for the next 251.

It also becomes the vi chord and then followed by 251

tritone substitution allows can be thought of allowing you to jump out of a key

sequencing is when you have the same chord progression but in a different key

lots of jazz music like big band plays the lead sheet twice, which is why they are usually exactly 3 minutes long

I'm being assigned the music Afternoon in Paris by John Lewis, I need to outline the 251s with parenthesis. I can do that by looking for major 7ths and working backwards