عمَل لا النافية للجنس في اسمها وتعليل تحديد البناء له أو الإعراب وفق نظريّة العمل عند نحْويّي القرون الوسطى

Abstract

Lā al-nāfiya li-ljins is annexed only to indefinite noun and used to negate the category (jins) of the noun that follows it. This particle comes at the head of nominal sentence and neutralizes the grammatical effect of ʼibtidāʼ, thus governing and assigning accusative case to the noun immediately following it, on analogy to the particle ʼinna.
On the one hand, the analogy to ʼinna is semantic: lā is considered as opposite of ʼinna in meaning and there is a doctrine that claims that the two opposites have the same grammatical effect. On the other hand, lā is analogous to ʼinna grammatically in that it occurs at the beginning of the sentence and requires two (nominal) constituents, subject and predication.
If the nominal component that follows lā al-nāfiya li-ljins is a single word, then its tanwīn must be dropped because it is annexed to lā and the word ending is determined by un-inflectional fatḥa, in contrast to the accusative case of that noun. This noun is called technically mabniyy (“uninflected”).
If the noun that follows lā al-nāfiya li-ljins is not a single word, then the word ending is determined by an inflectional marker realizing the accusative case. This noun is called muʽrab. The distinction here is between an annexed noun and a semi-annexed noun. In this case, there is no process of bināʼ because it is impossible to join three elements together into one syntactical phrase according to the theory.