By comparing nominal-appositive group in Persian and noun-appositive clauses in Arabic concerning definition, structure, usage, divisions ,arrange of parts, grammatical function ,being definite and indefinite, we see parallelisms and parallelisms.
The nominal-appositive group in Persian and nominal-appositive clause in Arabic are like each other in: 1. having two component including appositive converted part, 2. the ambiguity of appositive and disambiguation of converted part, 3. having no intermediator between the two part, 4. having the same antecedent and referring to the same referent . In addition in both languages, the converted part is benefited from appositive. The nominal-appositive group or clause can take most of the parts of speech in grammar too.
The difference is that unlike Arabic language, there is special pause between converted part and appositive in Persian language. In Arabic these two parts get the same role. It means appositive have the main role and converted part have the subordinate role. But in Persian language these two have a common grammatical function. In addition in nominal-appositive group in Persian, at least one of these two is definite, while in nominal–appositive clause in Arabic, one of these two components is not definite necessarily.
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