From: "Christophe Grandsire" <christophe.grandsire@...>
> En réponse à Balazs Sudar <conlang@...>:
> > What about two consonant roots? Do they need other rules, or they can be
> > used like tri-consonant roots?
>
> Usually they have other rules. But in Semitic languages biconsonantal
roots are
> rather exceptional, and don't have the same range of behaviour as the
> triconsonantal roots (mainly, they don't have as many derivations as
> triconsonantal roots). As far as I can tell, most biconsonantal roots
don't
> have much of derivatives.
In Arabic, Proto-Semitic bilaterals are often made into trilaterals by
doubling the second consonant or prefixing a glottal stop.
~Danny~