I do not see where a "laryngal" is needed since I believe the final long
*-a(:) was part of the simple root form.
If we add adjectival -*y to the full form, -*a: + -*y combines to form
*g^hlé:-; if we add the color formant -*w(o) to the full form, -*a: + -*w
combines to form *g^hló:-.
Patrick
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I don't think PIE, as a prehistorical stage,
had "natural" long vowels
that is to say vowels not rewrittable as v + H.
It's very "costly" from a descriptive point of view
to admit natural long vowels in PIE.
Which roots do you have that have the shape
C v: C ?
Such a form as *ghl-a:-w entails a syllabic structure
like CC-vv-C-
another costly hypothesis...
According to you,
in the word eight :
LAtin octâw-us should be octô.
As far as I know : it's octâvus.
I cannot see how a:+w can become o:
in either latin or greek.
> Arnaud
> ================