Motivations of " omission", advantages, condition and their kinds on syntax and eloquence

Briefness has two groups: shortness briefness and omission briefness, that both kinds have high position and a great impact on Arabic language. Omission means not to need word and this word could be a sentence, less than a sentence or more than that and these are the case that omitting a sentence is better than mention it. Omission has a tight and close relation to word means, implication and its power. Omission in syntax and eloquence is the same. The scientists of these two science paid attention on it from different aspects such as advantages, styles reasons, condition and divisions.The outcome of some of these different opinions are:- Some omission motivation are, contraction, easy to memorize near to understand, stricture of position, hiding something from a non-listener, avidness and learning intense meaning, from word is slender.- using omission in presenting affection, plain of feeling apologize, lugubrious is possible.- In syntax, most of the time there is no independent place for omission, however that omission in different field such as subject, verb, subject omission, object omission, is applicable.- Scientists of eloquence paid attention on the reason of omission. And mentioned points, in this regard and also rhetorical aspects at omission in Quran.- Among omission styles or adjectives styles, default or contraction there are differences. The mentioned points are specific secrets that depend on the position, feeling and word passion.