PowerPoint: Closed Captioning
Open the PowerPoint presentation to add closed captioning and select the Slide Show tab.
Select in the Captions & Subtitles section, check the box next to Always Use Subtitles.
Click the Subtitle Settings dropdown for more actions. You can change the language and customize where the subtitles appear on the screen.
Now, when presenting, hovering over the presentation will bring up the icons below. Click the Closed Captions icon to toggle subtitles on and off.
Overview
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