Part of editing your presentation is making sure that everything is spelled and assembled correctly. PowerPoint is a great help in this regard, because it can identify errors in your presentations. By default, PowerPoint checks for spelling errors as you type, underlining misspelled words in red.
In PowerPoint, your grammar is not automatically checked like it is in Word. You may find it helpful to turn grammar check on. Keep in mind that the grammar check only finds contextual errors, like the use of there/their/they’re, so you’ll still need to proofread for mistakes.
Click the File tab.
Click Options.
Click Proofing at the left.
Ensure the Mark grammar errors as you type box is checked.
Click OK.
Now grammatical errors will be treated like spelling errors. This means that they will be marked with a red wavy line and will be found when you check your spelling.