Momnotjon,
Not possible i'm afraid in PPT 2003.

You cant but this vba might interest you. Select a

Sorry  I didnt mean to post that!

This vba cuts lines beyond 6 from a placeholder that is selected and pastes
it into a placeholder on the target slide. Note the traget slide must exist
and be a title + text layout. This is pretty bare bones code and if you know
vba you can maybe play with it.

Sub linecut()
Dim imaxlines As Integer
Dim itarget As Integer
imaxlines = 6 'change the value if needed
itarget = InputBox("Target slide?")
On Error GoTo Err

With ActiveWindow.Selection.ShapeRange.TextFrame.TextRange
.Copy
.Lines(imaxlines + 1, .Lines.Count).Delete
End With
With
ActivePresentation.Slides(itarget).Shapes.Placeholders(2).TextFrame.TextRange
.Paste
.Lines(1, imaxlines).Delete
End With

Exit Sub
Err:
MsgBox ("Error, is anything selected?")
End Sub