What other rocks can form into metamorphic rocks due to regional metamorphism?

It is useful for historians to write narratives so that history can be passed on from their point of view.  think about a story being told in third person, then think about it again being told in first person, by someone who actually experienced the event.

What are the options?  

You need to attach a picture of said triangles for people to be able to you.

Points ab and d your welcome