It is very easy if you are using classic menu, just like working with Word 2003/2002/2000. Click the "Format" item on the main menu, you can see the "AutoFormat" item at the bottom.

It may be a bit difficult to know where AutoFormat is in Word 2007/2010/2013/2016 if you are not using Classic Menu for Office, but there are still a few ways to find it.

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