Nominal and verbal sentences represent central issues in arabic grammar theory, they discuss the positions of the noun and the verb as well as the harmony between nominal and verbal sentences, they show initial origins and their function that are manifest in etymological formulas and lexical and contextual characteristics indicated by a declension. The article discusses also the process of completeness and diminution in the noun and its classification in this duality by the coiners, and showing the role of nouns in building a meaning. Nominal and verbal structures are two important parts in language, based on activation of functional elements that are the dominance of rules and the greatness of realization.