CopyBlogger recently published a helpful infographic on common grammar errors. It provides a quick review and clarification I think you'll find helpful.
This infographic summarizes grammar errors Copyblogger encounters in online marketing writing. We commonly see these same errors in business writing, too.
However, two very prevalent business grammar errors weren't included in this infographic. These two errors, by far, are the most common errors we find when reviewing client documents. They comprise 30% of all errors we find.
Be certain your business documents do not include either of these prevalent business grammar errors: