I wish I could have seen the look on her face when she got my response: a link to the word "apropos" in the dictionary.
OK, I wasn't quite that flip about it. I buffered the stark simplicity of the information with some of my own words. But, really, all they amounted to was the qualifier "according to the dictionary ..."
Dictionaries aren't my only secret portal to the great mysteries of the grammar universe. I have others that are, in fact, a little less obvious. They're called usage guides. And for anyone who wants to become a grammar oracle in 10 seconds flat, they're gold mines.
You've probably seen usage guides without realizing it. They look a lot like dictionaries and sit right next to them in a lot of bookstores. In fact, my favorite usage guide has an unfortunate name that makes it all too easy to confuse with a regular dictionary. It's called Merriam-Webster's Dictionary of English Usage.
The best-known one is probably Fowler's Modern English Usage, and the most popular for American English is probably Garner's Modern American Usage.
Flip one open and you'll see just how different from dictionaries they are — and just what a genius your local grammar columnist isn't.
For example, thumb through the letter V in Garner's Modern American Usage and the following entry might catch your eye: "vicious circle; vicious cycle." In a few sentences you'll know that both forms are correct, but "vicious circle" is traditionally the more standard term.
Flip through Merriam-Webster's Dictionary of English Usage and you might land on an entry titled "possessive with gerund." Here you'll learn the difference between "I appreciate you taking the time to meet with me" and "I appreciate your taking the time to meet with me."