German nouns change their article depending on their grammatical role in the sentence ("case"). Accusative marks the direct object - the thing being had, bought, seen, wanted. At A1, only the masculine article actually changes.
| ich | habe |
| du | hast |
| er/sie/es | hat |
| wir | haben |
| ihr | habt |
| sie/Sie | haben |
Like sein, haben is irregular - the du/er forms (hast, hat) drop the -b-, so it doesn't quite follow the regular pattern from Lesson 3. It's the second irregular verb worth memorizing outright.
Compare nominative (subject - who/what is doing something) to accusative (direct object - who/what is being acted on):
| Gender | Nominative | Accusative | Change? |
|---|---|---|---|
| masculine | der / ein | den / einen | yes |
| feminine | die / eine | die / eine | no |
| neuter | das / ein | das / ein | no |
| plural | die | die | no |
This is genuinely good news: at A1, the only visible change is masculine der→den and ein→einen. Feminine, neuter, and plural articles look identical in nominative and accusative.
Ich habe einen Bruder. (der Bruder → einen, masculine accusative)
Ich habe eine Schwester. (die Schwester → unchanged)
Ich habe ein Kind. (das Kind → unchanged)
Ich kaufe den Tisch. (der Tisch → den, "the table" as a direct object)
Cross-checked against the Goethe-Institut A1 practice materials.