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Chapter 2 of 10All chapters

Chapter 2 of 10

Commas

Four jobs.

When to use one

Separating items in a list, joining two sentences alongside and or but, after an introductory phrase, and around a removable aside.

  • If a phrase can be lifted out without changing the meaning, fence it with commas.
  • The serial comma before the final and is optional and often clearer.

When not to

Never between a subject and its verb, and never joining two full sentences alone. If in doubt, read the sentence without the comma and see whether it changes.