Comma Rule 10: Commas with tag elements

A tag element is a phrase or word that is placed on the end of a sentence. They are "tagged" onto the end of the sentence.

Did you finish painting the deck, Riaz?

How com the house is burned down, Riaz?

A tag element comes right after a independent clause, if there is no independent clause, there is no need for the comma. A tag element cannot be proceeded by a verb or preposition. 

Walking down the strew like a cow. 

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