WHEN IS MIGHT RIGHT? This seems to be a problem for many writers -- witness a letter to the editor of the Toronto Star (the substance, but not the form, of the sentence has been changed to protect the innocent letter writer, who is after all not a professional): "We knew that if it rained the picnic might be cancelled and we may not see our friends."

Now, why on earth would she use might, correctly, in one clause, and then switch to may, incorrectly, in the exactly parallel clause that follows? Making a few discreet inquiries, I discovered that there are one or two people about who don't know that may and might are the same word, the present and past tenses thereof, to be precise. The letter writer probably thought she was introducing lively variety in vocab. In fact, in this context may is just wrong.

At its simplest, then, the may-might problem can be solved if you just remember that "Simon says that I may take one baby step" changes to "Simon said that I might take one baby step" in the past.

But it gets more confusing. May/might has two main meanings: it gives permission, and it indicates possibility. It's the latter that starts to cause trouble, because both forms of the word can be used to indicate possibility in the present -- or in the past. Might is also the subjunctive form, which means you can say "he may go to the theatre today" or "he might go to the theatre today." The difference in meaning is very slight, and both are grammatically correct. One presents a plain possibility, the other a hypothetical possibility, qualified by an implied condition (he might go to the theatre today, if he doesn't have to work).

The real problem begins with the fact that both may and might can also be used to indicate possibility in the past, and here the meaning is not comfortably close. What might have been is sharply, sometimes ludicrously, sometimes tragically different from what may have been.

What might have been can be an occasion for regret -- "The victim might have been saved if rescuers had arrived in time" (but they didn't) -- or relief -- "I might have been killed" (but I wasn't). When may have been is used to indicate possibilities in the past, it refers only to possibilities that remain open, unproven or unknown, as in "Pontius Pilate may have been born in Pitlochry, Scotland." This is where some writers blunder into saying things they can't possibly mean. Things like "I may have been killed." Obviously, you weren't. Or when journalists write such things as "with these precautions the disaster may have been averted." Well, was it averted or not? The reporter apparently doesn't know.

I know this kind of tortuous explanation is no substitute for hearing the correct forms used consistently, and sometimes I despair, but I think the distinction is so important that I slog on.

A LETTER TO THE EDITOR OF the Guardian Weekly objects to the spelling "Quebecers," which was used in a Washington Post item reprinted in the Guardian. The writer, Rodger Greig of Cherry Valley, Ontario, is fight: the word requires a k to indicate the correct pronunciation. There seems to be some kind of psychological resistance to the k. People think it looks funny. But truly, Quebecers looks even funnier, and it sounds awful. I think the resistance arises because it's only recently that the word Quebeckers came into common use. For much of their history the English speakers of this country called them "French Canadians" or (incorrectly) "the French," and left it at that. But now they are the Quebecois, and the term has to have an English equivalent. Quebecker, being fairly new, looks odd to some eyes, although much older words -- like mimicked and panicky -- which acquired the useful k long, long ago, have become comfortably familiar.

Maybe we should have left them their original name, "les Canadiens," instead of stealing it and applying it to the whole country, thereby providing them with yet another ground of resentment. I mean, imagine how we would feel if the United States annexed us and renamed the whole huge new country Canada.

PHRASES WITH ATTITUDE. Here are two remarkable examples of the metaphorically not-quite-there. A young movie actress was being interviewed on television about a horror movie she had appeared in. The script, she said, was so frightening "it would set your teeth on end." The other phrase was uttered by a vehement, irritated voice on the radio, describing some outrage that she claimed "got my backside up." Yikes.