You can set up a multilevel list, as Charles suggested, but you would have to insert a LISTNUM field to get the first "a" in the same paragraph as the level 1 number.

You can insert LISTNUM as follows: Press Ctrl+F9 to insert field delimiters, { }. Type in LISTNUM so that you now have { LISTNUM }. Press F9 to update. Right-click the field and use Increase Indent or Decrease Indent to change the list level for the field.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional