A family of Microsoft word processing software products for creating web, email, and print documents.
Contractions are (or used to be) discouraged in formal academic writing, so this is a "style" issue. Go to Office Button | Word Options | Proofing. Under "When correcting spelling and grammar in Word," you have several options:
- You can opt out of grammar checking entirely by clearing the check box for "Mark grammar errors as you type" and/or "Check grammar with spelling."
- If you enable grammar checking but select Grammar Only, Word won't flag contractions.
- But if you do want some style issues flagged, then click Settings... and, under Style, clear the check box for Contractions.