A Dozen Uses for Commas, Part 10

Commas can also be used at the end of sentences to separate contrast between coordinated elements or signal a pause or change in the direction of the sentence.

For example:

Her hands were cold, even freezing.

The oven was preheating, not just sitting empty.

She loved transcription, didn't she?

With all three of these sentences, you can hear a pause when you say them out loud, and the comma is used to signal that pause to the reader. In the first one, "cold even freezing" as a descriptive phrase, doesn't make much sense, but "cold, even freezing" is much easier for the reader to understand.