I am not sure I understand the question. You may want to submit the question again, telling us why you want this information.
You might want to start by reading up on phonetics a bit. Ladefoged's course on phonetics is available online, with sounds (http://www.phonetics.ucla.edu/course/...).
You need to:
Understand the difference between a phoneme and an allophone. For example, /p/ sounds quite different in 'pin', 'spin', and 'nip',
Understand allomorphs. For example, the plural (written as (e)s) is pronounced differently in 'cats', 'dogs', and 'horses'. This concept applies to the regular past tense.
Understand that there is dialectal variation in both phonemes and allophones.
Hope this helps. I am not sure what you mean by 'frequency' in this question.
Anthea Fraser Gupta
I can't answer your question with references either, off the top of my head, though as Dr. Fischer says there are such references available. In fact, with a little (OK, a lot of) study of the sound system of American English (btw, note also that there's no such thing, really: there is a vast array of different variants of 'American English', from 'Yankee' to 'Southern' to 'Midwest' to 'Western', and each one includes a wide variety of different 'accents', without even mentioning isolated variants like Ozark, Appalachian, etc. and others like 'Hispanic', 'Yiddish (English)', etc. Likewise, each of the varieties (mostly including a large geographic area each one) I have mentioned is itself divided into subvarieties. Indeed, in the focal, original areas of American English (for historical reasons, mostly found on or near the East Coast), even small areas can have a great variety of different ways of pronouncing the same words. One example: if we try to describe 'Philadelphia English', we need to take into account many different subvarieties: I remember one article about a kid who moved from one western (I think it was) suburb of Philadelphia to King of Prussia (which I'm not quite sure exactly where it is, but it is a suburb of Philadelphia) when she was six years old. Years later, natives of KofP could still tell she was not a native speaker of KofP English, although most linguists would consider six years old as plenty young enough to master natively a new language or dialect. In any case, the pronunciation differences, even between variants very close to one another indeed, is often detectable and therefore
describable; and there are huge numbers of such differences. Now, an Aussie, for example, would be unlikely to detect all these subtle differences and would mostly notice an 'American accent' only. So a separate issue would be the audience you are directing your study to.)
To return to the previous, interrupted sentence: you could take a speech synthesizer for American English (ie, a program that converts written text to speech, a much easier task than speech recognition), but it would have to be a very good one to capture all (or at least some ... (more)