Returns a Characters object that represents a range of characters within a shape’s text frame. You can use the Characters object to add and format characters within the text frame.
expression.Characters(Start, Length)
expression Required. An expression that returns a Characters object in the specified text frame.
Start Optional Variant. The first character to be returned. If this argument is either set to 1 or omitted, the Characters method returns a range of characters starting with the first character.
Length Optional Variant. The number of characters to be returned. If this argument is omitted, the Characters method returns the remainder of the string (everything after the character that was set as the Start argument).
Remarks
The Characters object isn't a collection.
Example
This example formats as bold the third character in the first shape’s text frame on the active worksheet.
With ActiveSheet.Shapes(1).TextFrame
.Characters.Text = "abcdefg"
.Characters(3, 1).Font.Bold = True
End With