Alternation ‘Causative’ (Coded)

Involves substituting transitive prefixes (and case frame) for basic middle set, without any other verbal marking (i.e. no diathetic prefix). Decision on which is basic is hard to give watertight arguments for, but in the case of e.g. armbs / warmbs there is an enormous difference in frequency, in favour of the middle form. However, it would still be possible to argue for another anlaysis in which the transitive form is basic, and the middle form is derived by the middle alternation. [But note if one adds wazrs 'pour' as an example - the only 'middle' alternation - then causatives can be defined as those where no diathetic prefix is involved, whereas those with a diathetic prefix always go the other way i.e. reduce valency by prefix