AA: I'm Avi Arditti with Rosanne Skirble, and this week on WORDMASTER: we talk with Pat O'Conner, co-author with her husband Stewart Kellerman of a new book called "Origins of the Specious: Myths and Misconceptions of the English Language."

RS: But first, here's a question for you. Which would you say, "All debts are cleared between you and I" or "All debts are cleared between you and me"? Is "I" or "me" the correct object? According to Pat O'Conner, for centuries either one would have been fine. Shakespeare, you should know, used "I" when he included that line in "The Merchant of Venice."

AA: But later the rule books got rewritten. Pat O'Conner says some people in the nineteenth century, probably influenced by rules for Latin, began to argue that "I" was wrong -- well, you know what I mean. Which leads to a question that Pat O'Conner gets asked a lot: who decides what's right? She says we all do.

Pat O'Conner and Stewart Kellerman

PAT O'CONNER: "Well, if something becomes a common enough usage, it becomes the accepted usage. Take the word 'agenda,' for instance. As recently as the nineteenth century it was a plural word. It meant the items on a list. Someone might have said to you 'What are your agenda for our meeting?' Later the word 'agenda' became used as a singular for the list itself rather than the items on the list.

"And similarly the words 'media' and 'data' are now changing. They're on the cusp of changing. 'Data,' I think, is over the edge. It's very seldom used as a plural anymore. Even the New York Times has changed its policy on that. It now has come to mean information as a whole."

RS: "How does a person learning English as a foreign language -- or someone who knows English quite well as a native speaker -- know what's right? It's not always what sounds right, or is it?"

PAT O'CONNER: "It depends on how well read you are, what you hear when you're growing up and those sorts of things. But I think for someone learning English as a second language, the best thing you can do is to acquire a good, up-to-date dictionary of American English -- say the American Heritage, fourth edition, or the Merriam-Webster 's Collegiate, eleventh edition, something like that that's always being updated. And always read the fine print. These things do change.

"For example, fifty years ago, if you looked in a dictionary for how to pronounce the word spelled n-i-c-h-e, you would have seen only one proper English pronunciation and that is 'nitch.' A lot of people don't realize this. They think that 'neesh' is the only correct pronunciation.

"In fact, 'neesh' evolved as an error. It was a Frenchification of the word. People looked at it, it looked French, they started pronouncing it as if it were French. It made it into dictionaries because it was so common, and now dictionaries give two pronunciations."

AA: "And you write that 'neesh' is now forcing out 'nitch.'"

PAT O'CONNER: "It is -- it's inching ahead!"

RS: "Something that we consider here at WORDMASTER very colloquial is 'ain't.' And according to your book, it hasn't always been considered bad English."

PAT O'CONNER: "No, it was formed around the early sixteen hundreds with a huge class of other contractions: don't, can't, isn't. And ain't was one of them. It was a contraction for two sets of words, for 'am not' and 'are not.' And it was originally spelled a'nt or a'n't. Perfectly legitimate.

"The problem was, in the late seventeen hundreds, people started using it as a contraction for 'is not.' And then in the eighteen hundreds they started using it as a contraction for 'have not' and 'has not,' as in 'I ain't got my wallet with me' or 'He ain't here.' Well, as soon as it got too big for its britches, ain't lost its reputation for legitimacy. Its parentage just could not be traced. And so it's been considered a grammatical no-no since sometime in the nineteenth century."

RS: Pat O'Conner's newest book is "Origins of the Specious: Myths and Misconceptions of the English Language." We'll talk more with her next time.

AA: And that's WORDMASTER for this week. With Rosanne Skirble, I'm Avi Arditti.