（標準モジュール）
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Sub PutPeriodToParagraphEnds()
Const PeriodCharacter As String = "。"
Dim strDocumentPath As String
With Application.FileDialog(msoFileDialogOpen)
.Filters.Clear
.Filters.Add "Word ドキュメント", "*.docx;*.docm;*.doc"
.AllowMultiSelect = False
If .Show = 0 Then
Exit Sub
End If
strDocumentPath = .SelectedItems(1)
End With
Dim docTarget As Word.Document
Set docTarget = Documents.Open(strDocumentPath)
Dim paraTarget As Word.Paragraph
Dim rngTarget As Word.Range
Application.ScreenUpdating = False
For Each paraTarget In docTarget.Paragraphs
Set rngTarget = paraTarget.Range
With rngTarget
.MoveEnd wdCharacter, -1
Select Case .Characters.Last
Case PeriodCharacter, vbCr, vbLf, vbCrLf, vbVerticalTab
'何もしない
Case Else
.InsertAfter PeriodCharacter
End Select
End With
Set rngTarget = Nothing
Next
Application.ScreenUpdating = True
docTarget.Activate
Set paraTarget = Nothing
Set docTarget = Nothing
End Sub
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以上のようなコードを実行できればよい、ということでしょうか。
