English - Punctuation - Comma usage - advanced (appositives, introductory phrases) - Advanced Comma Rules
6 steps: (1) APPOSITIVES: a noun phrase that renames another noun. Set off with commas: 'My brother, TOM, is a doctor.' 'TOM' renames 'my brother.' (2) ESSENTIAL vs NON-ESSENTIAL: If removing the appositive changes meaning, NO commas: 'My friend Tom called.' (I have many friends, specifying which on