FOC weeks 4-5 roles of facilitator, moderator and teacher

Try to determine the role and behavior of these three roles:

Facilitator
Moderator
Teacher

After quite a while of pondering and reading and fruitful conversations,  as well as a discarded post along the way, I now feel ready to tackle this task.
First, what are the roles of facilitator, moderator and teacher?  Defining what they are is perhaps a matter [...]