For presentations that contain slides with too much text, or even little text, there are always chances of spelling mistakes showing up! However, you don’t necessarily have to search for these mistakes by skimming all your slides one by one since PowerPoint lets you do a spell check of the entire presentation, and make corrections as well. However there are some caveats associated with spell checking, and this does not have anything to do with PowerPoint.
For more details, choose your version of PowerPoint:
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