الإعلال و الإبدال في الكافي للزنجاني (ت 655 ه)‎

الملخص EN

The explanation and substitution of important phoneme phenomena in the ancient linguistic lesson; Because they have an effect on changing the structure of the word, and the ancients set the general rules for them, and I followed the opinions of Al- Zanjani in the explanation and the substitution in his book (Al Kafi in Sharah Al-Hadi) and make a balance between the opinion of Al-Zanjani in Al Kafi and the opinion of the modernists to show a correct opinion according to convincing arguments.

Among the most important of these results: Most of the issues of explanation and substitution occurred as a result of forming hateful audio contexts such as long open or double- syllables, which creates a difficult in the pronunciation of those words, so the Arabic sought to get rid of these audio contexts by dropping them and replacing them with other voices.

The study proved that the substitution occurs between the sounds when there is a sound justification for that, such as their agreement in the director or the adjective, because the unity of the director or the adjective make substitution is among the most voices.