In what cases should I use a comma before "or"?

commas

You should not use it.

Generally, the rule of thumb is not to use a comma in sentences like yours when the second alternative is very short. Normally, this means that the sentence does not contain two subject/predicate combinations, such as:

  • Should I watch this movie on TV, or should I get my homework done?
  • You can wallow in self-pity, or you can stand up for yourself.

Avoid using commas to set off short phrases such as "or not." We don't write, for example, "Believe it, or not" or "Ready, or not."

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