Hello! I have wondered about this for a while, but have never found an answer to my question, mainly because I never asked for an answer to my question. Actually, I think I may already know the correct answer to my question, but I figured I might as well ask anyway. In the sentence, "First of all, my name is Amanda, but people call me Mandy." Would there be a comma between "all" and "my", or should that comma be deleted? I ask this because I know that introductory words are followed by a comma, however most people do not use the commas with introductory words, and it makes me wonder if the comma is actually necessary. Thank you in advance!
The initial phrase "First of all" acts adverbially on the whole sentence. It is the equivalent of putting a "1" in front of it:
1. My name is Amanda, but people call me Mandy.
It is therefore quite helpful to the reader if a comma follows it, to mark it off.
(In spoken English, you would pause after "all", with a distinctive intonation: this serves the same purpose as the comma in written English.)
Not a professional ESL teacher.