Check the spelling in a presentation in Keynote for iCloud
You can turn on the spell checker so that misspelled words are displayed with a red dotted underline, and suggested corrections are shown.
Note: The spell checker is only available for only some languages. If misspelled words aren’t underlined or if the suggestions seem wrong, spell check might not be available for the language you’re using.
Click the Tools button
in the toolbar, then choose Preferences.Make sure the “Check spelling while typing” checkbox is selected.
As you type in your presentation, click any underlined (misspelled) word, then do one of the following:
Click the suggested spelling you want to use.
Type a new word over the misspelled word.
To turn off the spell checker, click the Tools button in the toolbar, choose Preferences, then deselect the “Check spelling while typing” checkbox.