Which case governs a direct object in a Polish sentence containing a negated transitive verb?

In a Polish sentence containing a negated transitive verb, the direct object is governed by the Genitive case. A transitive verb is a verb that takes a direct object, meaning it acts upon something or someone. A direct object is the noun or pronoun that receives the action of the verb directly. Negation is the act of making a sentence negative, usually by adding 'nie' (not) before the verb. Normally, direct objects in Polish sentences are in the Accusative case. However, when a transitive verb is negated, the direct object shifts to the Genitive case. This change is obligatory. For example, consider the sentence 'Ja czytam książkę' (I am reading a book), where 'książkę' (book) is in the Accusative case. When negated, the sentence becomes 'Ja nie czytam książki' (I am not reading a book), and 'książki' (book) changes to the Genitive case. This rule applies broadly to all transitive verbs when they are negated, demonstrating a key feature of Polish grammar.