Here’s an intriguing example of when not to use a comma:
The secret pact that had saved them in their turbulent adolescent years, could spell his doom now.
Do you see the problem? The comma interrupts the flow of the sentence by popping up right before the verb phrase, “could spell his doom.” The sentence should read like this:
The secret pact that had saved them in their turbulent adolescent years could spell his doom.
Tara’s Writing Studio