Do you use a comma before naming?

You're asking about commas in a sentence when you're introducing someone. Here's the breakdown:

You generally don't use a comma before naming someone.

Examples:

* Correct: I met your brother, John, at the party.

* Correct: The person I want to introduce you to is my friend, Sarah.

Exceptions:

* When the name is in apposition:

* "My best friend, John, is coming to visit." Here, "John" is in apposition to "my best friend," clarifying who you are referring to.

* For emphasis or clarity:

* "I met the president, you know, the one with the funny hat."

* "The new employee, Mary, is a computer expert."

Remember: It's important to use commas correctly to make your writing clear and easy to read. If you are unsure about whether or not to use a comma, it's always best to consult a grammar guide or style manual.