?Naro cel ei nau cepoa sia? ['naru,gil enQ,gibua'Za]

> Yes, the letter |t| represents the phoneme /t/, and |tt| is
> simply that phoneme twice /tt/.  In a medial position, the
> difference is
> obvious: |ata| [a.da] vs. |atta| [at.ta].  In the initial
> position, they both sound the same: |ta| [ta], |tta| [ta],
> but phrasal medialisation can make the difference audible
> again: |o ta| [u.da],
> |o tta| [ut.ta].  In final position, |tt| is not allowed.
>
> I guess it would also be valid from a linguistic point of
> view to define |t| and |tt| as a phoneme each, but that's not
> the way the Tao Ttouans see it.  ;-)
On the other side of the sword, I disagree that they behave like
distinct phonemes, based on my loose understanding of the idea of
phoneme.  My grounds: Taot Toua and Tao Ttoua both result in |tt|
behavior, regardless of morpheme/syllable boundaries.  This suggests to
me that |tt| is a cluster, rather than a phoneme in its own right.  Were
it phonemic, I'd expect to find a distinction between the two
pronunciations (maybe [taut.toa] vs. [tau.toa]).  Compare English
"guano" /b&t.SIt/ vs. */b&tS)It/.
Forgive me for being non-rigorous, as usual.

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Shreyas Sampat