Q. One of my supervisors—a former English teacher—insists that the comma and semicolon in the following sentence are correct. I have no intention of arguing the point, but I would love to learn the rule so I don’t make the mistake again. (Yes, I’m too intimidated to ask him directly.) Is this sentence correctly punctuated, in your view? “Your professionalism supports our record for safety and quality, advances our worldwide reputation; and helps us to grow as an industry leader.”

A. Oh, my, no—it’s not correct. Don’t underrate yourself. This is a fairly wacko use of the semicolon. It should be a simple serial comma.