Phoneme And Allophones

[dsfbrit]

A Thai friend of mine is in Sydney and struggling with her homework. I have helped with 4 of the questions, but am weak on Phonetics.

I would appreciate any comments on what I have written already. I have got most of my recent rapidly acquired knowledge from Wikipedia, I am no expert on this at all. Once I have understood it I will try to explain it all to her - the poor kid is in tears trying to understand it . Thanks for any feedback.

Here is the question and my partial (poor attempt) at a reply:

Question

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Given the following set of data, explain the distribution of [a] and [ã]; are they allophones of one phoneme, or contrasting sounds? If allophones, describe their distribution.

carton [katen] smart [smat]

laugh [laf] can’t [kãnt]

task [task] sample [sãmpel]

cart [kat] calm [kãm]

Answer So far

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- The distribution of non-aspirated [a] is anywhere and for the nasalised [ã], is before a nasal consonant.

- Any group of related sounds which are phonetically different but are treated as equivalent in a particular language is a PHONEME of that language. And the sounds themselves, the “members of the family”, are called ALLOPHONES of the phoneme. In this case both [ã] and [a] are allophones of the phoneme /a/.

- [a] and [ã] have a complementary distribution.