Try something along the lines of:
Code:
Sub ChangeAPA2toAPA3()
'
' ChangeAPA2toAPA3 Macro
' Changes from freestanding APA 2 level subhead to run-in APA level 3 subhead.
' Uses BodyText style to define the trailing paragraph style.
'
With Selection
.Font.Reset
With .Paragraphs.Last
.Style = "Body Text"
.Range.Case = wdLowerCase
.Range.Case = wdTitleSentence
End With
With .Paragraphs.First
.Style = "Heading 3"
End With
.Collapse wdCollapseStart
.InsertStyleSeparator
End With
End Sub
Note: The above code assumes you've already split the heading & run-in text into two paragraphs. If you're trying to apply bolding to the "Heading 3" content, that should be done via a change in the Style definition; if you're doing it to the run-in text, you should apply the "Strong" Style to that.