Besides Spell check, you can use the Grammar check. Just click on the Review tab, and then Spelling and Grammar.
Grammar check can look for capitalization, fragments and run-ons, improper possessives and plurals, incorrect punctuation, subject-verb agreement, passive voice and a lot more. You can pick what grammar check will look for:
In Word, click on File>Options (lower left)>Proofing>When Correcting Spelling and Grammar in Word>Writing Style>Settings.
The Redbook by 
Modern English Usage, 4th ed. by 
