Just about every week, GrammarBook.com receives emails like this: “My brilliant ninth-grade English teacher drilled into us that so-and-so, but now you say such-and-such.” The painful truth is that with each new generation the rules change.

If you were in high school in the 1970s, it’s a safe bet that your brilliant English teacher lectured you about the word hopefully. Forty years ago this word polarized America. People loved to say it, and language snobs loved to hate it. The veteran TV journalist Edwin Newman had a sign in his office that said, “Abandon ‘hopefully’ all ye who enter here.”

Nobody claimed that hopefully was invalid—it was the way everyone used it that was unacceptable. The word’s strict meaning is “filled with hope,” as in Hopefully, I knocked on my true love’s door. But few used it that way. It came to mean “it is hoped that,” as in Hopefully, my dream will come true.

The authorities were up in arms for several reasons. For starters, hopefully became a fad word, like today’s awesome or amazing. You couldn’t walk down the street without hearing it everywhere. The more people said it, the more grating and vapid it became.

Beyond that, language scholars saw hopefully as a cop-out—no more than a glib way of avoiding “I hope.” It’s intentionally unclear who is hoping in Hopefully, my dream will come true. The word just floats there, unattached. Are you saying the whole universe hopes your dream will come true? Are you really that special?

Those who weren’t there can’t know how passionately the sticklers despised hopefully. “Its detractors were operatic in their vilifications,” says writer Geoff Nunberg. The odd thing was that the same detractors had no objection to other “floating” adverbs, such as thankfully, happily, and frankly.

For decades the venerable Associated Press Stylebook said in its entry on hopefully: “It means in a hopeful manner. Do not use it to mean it is hoped, let us hope or we hope.” So imagine the surprise of many who opened the 2012 edition and found this: “The traditional meaning is in a hopeful manner. Also acceptable is the modern usage: it’s hoped, we hope.”

Now, after all these years, the uproar is a dim memory, and the word is accepted in most quarters (although you will never see a floating hopefully in this space).

So much for that English teacher’s scolding in 1979. To the dismay of traditionalists, a language’s rules are bound to change when enough people refuse to obey them.