ein. eine. kein.
The indefinite articles.
ein and eine mean "a" or "an". They decline across all four cases the same way der, die, das do, with the same six endings doing the same jobs. But the indefinite article has a hole where the plural should be: there is no German word for "some a's". That hole is exactly where kein, the negative article, becomes essential.
The starting point: ein and eine
In the Nominativ, ein covers both masculine and neuter, while eine covers feminine. Unlike der · die · das · die, there is no fourth row for the plural. ein and eine are, by definition, about exactly one of something.
| Gender | Nominativ | Example |
|---|---|---|
| Masculine | ein | einMann |
| Feminine | eine | eineFrau |
| Neuter | ein | einKind |
| Plural | no indefinite article | |
The full table: ein across the four cases
The endings that attach to ein- are the same endings that turn der into den, dem, and des. der already ends in those sounds, so it just changes. ein- has nothing to lose, so the ending is simply added on.
| Case | Masculine | Feminine | Neuter |
|---|---|---|---|
| Nominativ | ein | eine | ein |
| Akkusativ | einen | eine | ein |
| Dativ | einem | einer | einem |
| Genitiv | eines (+es) | einer | eines (+es) |
Lined up next to der · die · das, the pattern is the same shape. den and einen share the same -en. dem and einem share -em, der and einer share -er. des and eines share -es. Learn the definite article, and the indefinite endings come almost for free.
- Ich seheeinenHund. → Akkusativ masculine
- Ich helfeeinerFrau. → Dativ feminine
- Das istdasSpielzeug einesKindes. → Genitiv neuter, +es on the noun
The missing plural, and how kein fills it
English can say "a book" and "no books" with the same little word, "a" and "no". German cannot. ein simply stops existing in the plural. A German plural noun phrase is either definite, with die, or it carries no article at all. kein, however, declines exactly like ein- in the singular, and then continues into a plural that ein- never had → keine.
| Case | Masculine | Feminine | Neuter | Plural |
|---|---|---|---|---|
| Nominativ | kein | keine | kein | keine |
| Akkusativ | keinen | keine | kein | keine |
| Dativ | keinem | keiner | keinem | keinen (+n) |
| Genitiv | keines (+es) | keiner | keines (+es) | keiner |
- Ich habeeinenBruder. Ich habekeinenBruder. → singular, ein → kein
- Ich habeGeschwister. Ich habekeineGeschwister. → plural, no article → keine
The plural row of kein follows the same plural pattern as der · die · das: it borrows the feminine singular shape, keine, keine, keiner, with the Dativ plural keinen standing apart and adding -n to the noun.
ein-words: possessives follow the same pattern
The possessive pronouns mein, dein, sein, ihr, unser, euer, and Ihr decline by attaching exactly the same endings as ein- and kein-. Once the ein- table above is familiar, these come for free, just with a different stem at the front.
- mein Hund → Nominativ, like einHund
- meinen Hund → Akkusativ, like einenHund
- meinem Hund → Dativ, like einemHund
- meines Hundes → Genitiv, like einesHundes
And unlike ein-, the possessives do have a plural, formed the same way kein forms its plural → meine Hunde, meinen Hunden.
For the full set of possessives in every person: Possessive pronouns. Whose is it?
ein- declines like der · die · das with endings added rather than swapped → -en, -em / -er, -es / -er. But ein- has no plural at all. kein follows the exact same singular pattern and then adds the plural keine, the only plural this family has. The same endings reappear a third time on the possessives mein, dein, sein, ihr, unser, euer, Ihr, which, unlike ein-, do have a plural of their own.
For the definite article across all four cases: der, die, das. Articles and the four cases. For the bigger picture on word classes: Artikel. Three jobs in one syllable. And for how the number eins turns into ein- before a noun: Numerale. The words that count. To negate a noun phrase entirely, kein steps in for ein and eine, see nicht vs. kein. Two ways to say "no."