Duplicate slides within a presentation
To add a slide that contains the content of an existing slide in a presentation, you can duplicate the slide.
In the pane that contains the Outline and Slides tabs, click the Slides tab.
Select one or more slides that you want to duplicate.
On the Home tab, in the Slides group, click New Slide.
In the layout gallery, click Duplicate Selected Slides.
Note The duplicated slides are inserted directly below the lowermost slide that you selected.