> Well, maybe I should just ask: "How does one conjugate an a-grade
> verb across the whole aspectual spectrum of durative, aorist and
> stative?"
According to Rix, *mad shows:
(a) zero grade (with a coloured schwa) + -ye suffix: OIr -maid
"shatters"
(b) ? redpulicated o-grade perfect: OIr ro:mmemaid "is broken"
(c) zero grade (with a coloured schwa) + -h1ye suffix: Latin madeo "be
wet"
(don't blame me for his suffix - I'd've gone with *mad-eye
causative)
There are also adjective forms e.g. Greek /madaros/ = "wet" and the
denominative /madaw/ = "be wet"
In addition, for some other -a- verbs, Rix offers:
aorist *mag' > mag'-/m.g'
present *magh > magh+medial endings (statives)
causative *masd > mosd-eye
etc
So to answer your general query, for -a- verbs we can suggest:
present C(a)C + suffix (-ye / -h1ye / -n-ye ....)
aorist CaC/CC- (strong and weak stems)
perfect Ce-CoC-
stative CaC + mediopassive endings
causative CoC-eye
Peter