Introduction to the Morphophonemic Rules

There are a few letters in the language such that, if they are part of the base letters of a word, the word is considered weak. If a verbs is considered weak, a set of rules must be applied in order to change it so that it is no longer considered such. This discussion is mainly focused on three-lettered words, and we begin with verbs and then extend our knowledge to nouns later.

 

Below is a chart that gives these letters

 

Name of the Set of Rules Applied to this Type of Verb	Name Given to the Verb that has this		Week Letter (and where it Occurs in the Verb)
—	صحيح		None of the below
تخفيف	الأفعال المهموزة		همزة anywhere in the base
تعليل or إعلال	الأفعال المعتلّة	أفعال المثال	واو or ياء in the first position
		الأفعال الجوفاء	واو or ياء in the second position
		الأفعال الناقصة	واو or ياء in the third position
		أفعال اللفيف	واو or ياء in multiple positions
إدغام	الأفعال المضاعفة		the second and third letters are the same

 

There are at least 50 rules that govern what will happen when these letters occur in a word, based on surrounding letters, vowels, etc. However, when we study basic morphology, we only discuss at most 10 of these as they account for the vast majority of these occurrences.

 

The classification of words based on weak letters is parallel to their classification based on templates. This means that a word will have both a template as well as a weak-letter classification. For example, the verb قال (he said) is on the pattern فَعَلَ and, in terms of its weakness, it is among the الأفعال الجوفاء.