Q: When I was in grade school, we were taught one NEVER begins a sentence with "And" or "But." Can you offer a definitive statement on this roiling controversy? I also have another question: When is it proper to use "further" and/or "farther"? The dictionary seems to say they are interchangeable. — JR, Greensburg, Pa.

A. Ah, yes. Teachers and dictionaries ... Both are generally reliable guides to usage standards, but both can also be wrong.

As your reference to grade school suggests, the prohibition on beginning sentences with "And" and "But" was first imposed among the blackboards and yellow pencils of our primary classrooms. (Remember the smell of a freshly-sharpened pencil?)

Our teachers worried we would write sentences that mimicked our breathless speech, e.g., "Tommy told me that he was there. And he saw the puppies. But he couldn't pet them ..."

So these well-meaning mentors decreed that we should never start our sentences with "And" or "But." But you can now store their antique prohibition away in the attic.

In fact, opening a sentence with "And" is a powerful tool for presenting successive pieces of evidence ("And that's not all!") or connecting sequential events or ideas ("And God said, 'Let there be light'").

And the sentence-opening "But" is effective for presenting sharp contradiction. Thomas Jefferson's Declaration of Independence shattered every tea cup in England with a sentence that began, "But when a long train of abuses and usurpations . . ." It was the "But" heard 'round the world.

As for "further" and "farther," it's true that these words were once used interchangeably. But during the past few centuries, a distinction has emerged between them.

Most usage authorities insist that "farther" be used for physical distance, e.g., "London is farther away than Philadelphia," and that "further" be used for figurative distance, e.g., "Let's delve further into the subject." (Handy mnemonic: "physical" and "farther" share an "a"; "figurative" and "further" share a "u.")

Sometimes the concepts of physical and figurative distance do overlap, e.g., "George's transfer to California left him and his brother (further/farther) apart." But generally the choice is clear.

The folks in our Mother Country, God bless 'em, continue to make no distinction between the two words. So preserving this differentiation in the U.S. is something of a linguistic Declaration of Independence.

Rob Kyff, a teacher and writer in West Hartford, Conn., invites your language sightings. Send your reports of misuse and abuse, as well as examples of good writing, via email to Wordguy@aol.com or by regular mail to Rob Kyff, Creators Syndicate, 737 3rd Street, Hermosa Beach, CA 90254.