WILLIAM LABOV: Someone says 'gee, I got to find a coffee shop,' and someone said 'but you already had your coffee.' The people who would normally expect that 'copy shop' would be different from 'coffee shop' are quite confused when they enter an area where both are pronounced with the same vowel.

RS: As were we right now.

AA: So copy -- there are some Americans who say 'coffee' and 'copy' the same?

WILLIAM LABOV: Well, the vowel will be the same; the 'p' and 'f' differences are hardly worth noticing in rapid speech. But the vowels will be identical for the people who come from Pittsburgh or from Montreal.

People have a great tendency to think our language works better than it does. So when we ask people to keep track of the number of misunderstandings that occur in the course of a day, there are quite a few. But if you ask them to remember them, they don't.

AA: Yet there may be more and more misunderstandings. Professor Labov says many local dialects are dying out and regional ones are growing stronger.

WILLIAM LABOV: We have plenty of real-time studies to show that these changes are moving on so that the dialects of the United States are more different from each other now than they were 100 years ago.

RS: That's so surprising, given that we travel so much.

AA: And given that we hear each other so much more now through radio and television.

RS: And even the Web.

WILLIAM LABOV: Well, one of the things that social psychology has told us, and many other branches of study, is that listening passively to the radio and television doesn't change your behavior. You're influenced by the people you speak with in daily interaction face-to-face.

AA: Now you've done a lot of research on the influence of women as a driving force in sound change, have you not?

WILLIAM LABOV: Yes, the difference between men and women is really important, and it's an astonishingly powerful force in most of the changes that we've talked about. In about 90 percent of them, women are way ahead of men -- a full generation ahead.

RS: Now what is your explanation for -- you say it's who you interact with. But we are very mobile people. We go from coast to coast. We take a job in one city and then another. We're taking our language with us and interacting with people on business trips and such.

WILLIAM LABOV: Well, almost everybody will tell you, 'Oh, I'm a regular chameleon. I change my speech according to who I'm talking to.' That's a great exaggeration. The fundamental pattern that you learned as a child stays with you pretty much for the rest of your life.

AA: Now, Doctor Labov, I'm curious, let's take an example like Southern California or other parts of the country where there's a large number of immigrants, and so you've got different languages and different sounds and dialects all coming together. What effect are you seeing?

WILLIAM LABOV: Well, people used to think that the American dialects are the result of all the immigrants coming in. And that turns out to be just the opposite. Gender has a big influence on the way you speak, your social class, what city you're living in.

But the language spoken by your parents has almost no influence in most areas, so that the people whose parents spoke Italian or Yiddish or German or Irish, now in the second or third generation will speak almost the same. That's the powerful assimilationist tendency in the United States.

There is one exception to that, and you mentioned Southern California. For the first time we are getting a native type of English which shows a certain amount of ethnic difference, and that's the people whose parents spoke Spanish and who may have grown up themselves speaking Spanish.

AA: Can you give us an example or two?

WILLIAM LABOV: Let's take the pronunciation of a word like card, and old. Most Americans will sometimes drop the d in old, and you'll see this when you read a novel, 'good ol' Joe,' o-l apostrophe. But Americans never drop the d when it comes after an r, so you don't talk about a 'car game' for a 'card game.' Nobody will say 'I had a har time' for 'a hard time.' But Latino speakers will do this.

These are small differences. We still don't know what the future holds for us with the large Asian group that's coming in the United States. But in every community there are some groups who assimilate totally and become absolutely natural speakers of that local dialect, and others who become native speakers but not really local.

AA: University of Pennsylvania linguist William Labov is the project director for the forthcoming Atlas of North American English. You can learn more about this project from a link at our Web site. The address is voanews.com/wordmaster. And our e-mail address is [email protected]. With Rosanne Skirble, I'm Avi Arditti.