475: Circle Theorems

Here are eight circle theorems, written by a Brit so you'll have to "translate" to American English ...
Are these the most important ones?
Are there any that are missing that you feel should be included in this group?

source:

Circle Theorems - these are very important to learn for the Higher Tier pic.twitter.com/rG4KOwwixP

— Corbettmaths (@Corbettmaths) May 31, 2015